diff --git a/README.md b/README.md
index 90afdab3..8ee0c4af 100644
--- a/README.md
+++ b/README.md
@@ -180,6 +180,13 @@ There are three different kinds of messages:
 
 There is also an implicit message which closes the queue which will cause the sender thread to finish processing and exit.
 
+
+```ruby
+statsd = Datadog::Statsd.new('localhost', 8125)
+```
+
+The message queue's maximum size (in messages) is given by the `sender_queue_size` argument, and has appropriate defaults for UDP (2048) and UDS (512).
+
 The `buffer_flush_interval`, if enabled, is implemented with an additional thread which manages the timing of those flushes.  This additional thread is used even if `single_thread: true`.
 
 ### Usual workflow
diff --git a/lib/datadog/statsd.rb b/lib/datadog/statsd.rb
index 6c8c3861..e0f1f28d 100644
--- a/lib/datadog/statsd.rb
+++ b/lib/datadog/statsd.rb
@@ -45,7 +45,12 @@ class Error < StandardError
     UDP_DEFAULT_BUFFER_SIZE = 1_432
     UDS_DEFAULT_BUFFER_SIZE = 8_192
     DEFAULT_BUFFER_POOL_SIZE = Float::INFINITY
+
+    UDP_DEFAULT_SENDER_QUEUE_SIZE = 2048
+    UDS_DEFAULT_SENDER_QUEUE_SIZE = 512
+
     MAX_EVENT_SIZE = 8 * 1_024
+
     # minimum flush interval for the telemetry in seconds
     DEFAULT_TELEMETRY_FLUSH_INTERVAL = 10
 
@@ -74,6 +79,7 @@ def tags
     # @option [Logger] logger for debugging
     # @option [Integer] buffer_max_payload_size max bytes to buffer
     # @option [Integer] buffer_max_pool_size max messages to buffer
+    # @option [Integer] sender_queue_size size of the sender queue in number of buffers (multi-thread only)
     # @option [Numeric] buffer_flush_interval interval in second to flush buffer
     # @option [String] socket_path unix socket path
     # @option [Float] default sample rate if not overridden
@@ -92,6 +98,8 @@ def initialize(
       buffer_overflowing_stategy: :drop,
       buffer_flush_interval: nil,
 
+      sender_queue_size: nil,
+
       logger: nil,
 
       single_thread: false,
@@ -138,6 +146,8 @@ def initialize(
         buffer_overflowing_stategy: buffer_overflowing_stategy,
         buffer_flush_interval: buffer_flush_interval,
 
+        sender_queue_size: sender_queue_size,
+
         telemetry_flush_interval: telemetry_enable ? telemetry_flush_interval : nil,
       )
     end
diff --git a/lib/datadog/statsd/connection.rb b/lib/datadog/statsd/connection.rb
index 2a8f999a..35adbbc6 100644
--- a/lib/datadog/statsd/connection.rb
+++ b/lib/datadog/statsd/connection.rb
@@ -38,7 +38,7 @@ def write(payload)
           end
         end
 
-        telemetry.dropped(packets: 1, bytes: payload.length) if telemetry
+        telemetry.dropped_writer(packets: 1, bytes: payload.length) if telemetry
         logger.error { "Statsd: #{boom.class} #{boom}" } if logger
         nil
       end
diff --git a/lib/datadog/statsd/forwarder.rb b/lib/datadog/statsd/forwarder.rb
index 0d3c2852..dcbd53ed 100644
--- a/lib/datadog/statsd/forwarder.rb
+++ b/lib/datadog/statsd/forwarder.rb
@@ -14,6 +14,8 @@ def initialize(
         buffer_overflowing_stategy: :drop,
         buffer_flush_interval: nil,
 
+        sender_queue_size: nil,
+
         telemetry_flush_interval: nil,
         global_tags: [],
 
@@ -49,7 +51,21 @@ def initialize(
           max_pool_size: buffer_max_pool_size || DEFAULT_BUFFER_POOL_SIZE,
           overflowing_stategy: buffer_overflowing_stategy,
         )
-        @sender = (single_thread ? SingleThreadSender : Sender).new(buffer, logger: logger, flush_interval: buffer_flush_interval)
+
+        sender_queue_size ||= (@transport_type == :udp ?
+                               UDP_DEFAULT_SENDER_QUEUE_SIZE : UDS_DEFAULT_SENDER_QUEUE_SIZE)
+
+        @sender = single_thread ?
+          SingleThreadSender.new(
+            buffer,
+            logger: logger,
+            flush_interval: buffer_flush_interval) :
+          Sender.new(
+            buffer,
+            logger: logger,
+            flush_interval: buffer_flush_interval,
+            telemetry: @telemetry,
+            queue_size: sender_queue_size)
         @sender.start
       end
 
diff --git a/lib/datadog/statsd/sender.rb b/lib/datadog/statsd/sender.rb
index e96a11d1..ede41980 100644
--- a/lib/datadog/statsd/sender.rb
+++ b/lib/datadog/statsd/sender.rb
@@ -12,10 +12,14 @@ class Statsd
     class Sender
       CLOSEABLE_QUEUES = Queue.instance_methods.include?(:close)
 
-      def initialize(message_buffer, logger: nil, flush_interval: nil)
+      def initialize(message_buffer, telemetry: nil, queue_size: UDP_DEFAULT_BUFFER_SIZE, logger: nil, flush_interval: nil, queue_class: Queue, thread_class: Thread)
         @message_buffer = message_buffer
+        @telemetry = telemetry
+        @queue_size = queue_size
         @logger = logger
         @mx = Mutex.new
+        @queue_class = queue_class
+        @thread_class = thread_class
         if flush_interval
           @flush_timer = Datadog::Statsd::Timer.new(flush_interval) { flush(sync: true) }
         end
@@ -45,7 +49,7 @@ def rendez_vous
         return unless message_queue
 
         # Initialize and get the thread's sync queue
-        queue = (Thread.current[:statsd_sync_queue] ||= Queue.new)
+        queue = (@thread_class.current[:statsd_sync_queue] ||= @queue_class.new)
         # tell sender-thread to notify us in the current
         # thread's queue
         message_queue.push(queue)
@@ -75,16 +79,20 @@ def add(message)
           }
         end
 
-        message_queue << message
+        if message_queue.length <= @queue_size
+          message_queue << message
+        else
+          @telemetry.dropped_queue(packets: 1, bytes: message.bytesize) if @telemetry
+        end
       end
 
       def start
         raise ArgumentError, 'Sender already started' if message_queue
 
         # initialize a new message queue for the background thread
-        @message_queue = Queue.new
+        @message_queue = @queue_class.new
         # start background thread
-        @sender_thread = Thread.new(&method(:send_loop))
+        @sender_thread = @thread_class.new(&method(:send_loop))
         @sender_thread.name = "Statsd Sender" unless Gem::Version.new(RUBY_VERSION) < Gem::Version.new('2.3')
         @flush_timer.start if @flush_timer
       end
@@ -131,7 +139,7 @@ def send_loop
             case message
             when :flush
               message_buffer.flush
-            when Queue
+            when @queue_class
               message.push(:go_on)
             else
               message_buffer.add(message)
@@ -153,7 +161,7 @@ def send_loop
               break
             when :flush
               message_buffer.flush
-            when Queue
+            when @queue_class
               message.push(:go_on)
             else
               message_buffer.add(message)
diff --git a/lib/datadog/statsd/telemetry.rb b/lib/datadog/statsd/telemetry.rb
index 54b45366..89b19357 100644
--- a/lib/datadog/statsd/telemetry.rb
+++ b/lib/datadog/statsd/telemetry.rb
@@ -9,8 +9,12 @@ class Telemetry
       attr_reader :service_checks
       attr_reader :bytes_sent
       attr_reader :bytes_dropped
+      attr_reader :bytes_dropped_queue
+      attr_reader :bytes_dropped_writer
       attr_reader :packets_sent
       attr_reader :packets_dropped
+      attr_reader :packets_dropped_queue
+      attr_reader :packets_dropped_writer
 
       # Rough estimation of maximum telemetry message size without tags
       MAX_TELEMETRY_MESSAGE_SIZE_WT_TAGS = 50 # bytes
@@ -40,8 +44,12 @@ def reset
         @service_checks = 0
         @bytes_sent = 0
         @bytes_dropped = 0
+        @bytes_dropped_queue = 0
+        @bytes_dropped_writer = 0
         @packets_sent = 0
         @packets_dropped = 0
+        @packets_dropped_queue = 0
+        @packets_dropped_writer = 0
         @next_flush_time = now_in_s + @flush_interval
       end
 
@@ -54,9 +62,18 @@ def sent(metrics: 0, events: 0, service_checks: 0, bytes: 0, packets: 0)
         @packets_sent += packets
       end
 
-      def dropped(bytes: 0, packets: 0)
+      def dropped_queue(bytes: 0, packets: 0)
         @bytes_dropped += bytes
+        @bytes_dropped_queue += bytes
         @packets_dropped += packets
+        @packets_dropped_queue += packets
+      end
+
+      def dropped_writer(bytes: 0, packets: 0)
+        @bytes_dropped += bytes
+        @bytes_dropped_writer += bytes
+        @packets_dropped += packets
+        @packets_dropped_writer += packets
       end
 
       def should_flush?
@@ -70,8 +87,12 @@ def flush
           sprintf(pattern, 'service_checks', @service_checks),
           sprintf(pattern, 'bytes_sent', @bytes_sent),
           sprintf(pattern, 'bytes_dropped', @bytes_dropped),
+          sprintf(pattern, 'bytes_dropped_queue', @bytes_dropped_queue),
+          sprintf(pattern, 'bytes_dropped_writer', @bytes_dropped_writer),
           sprintf(pattern, 'packets_sent', @packets_sent),
           sprintf(pattern, 'packets_dropped', @packets_dropped),
+          sprintf(pattern, 'packets_dropped_queue', @packets_dropped_queue),
+          sprintf(pattern, 'packets_dropped_writer', @packets_dropped_writer),
         ]
       end
 
diff --git a/spec/integrations/allocation_spec.rb b/spec/integrations/allocation_spec.rb
index 02b8477f..8751e6e7 100644
--- a/spec/integrations/allocation_spec.rb
+++ b/spec/integrations/allocation_spec.rb
@@ -44,11 +44,11 @@
 
     let(:expected_allocations) do
       if RUBY_VERSION < '2.4.0'
-        16
+        20
       elsif RUBY_VERSION < '2.5.0'
-        15
+        19
       else
-        14
+        18
       end
     end
 
@@ -72,13 +72,13 @@
 
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          8
+          12
         elsif RUBY_VERSION < '2.5.0'
-          7
+          11
         elsif RUBY_VERSION < '2.6.0'
-          6
+          10
         else
-          5
+          9
         end
       end
 
@@ -93,13 +93,13 @@
     context 'with tags' do
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          25
+          29
         elsif RUBY_VERSION < '2.5.0'
-          23
+          27
         elsif RUBY_VERSION < '2.6.0'
-          22
+          26
         else
-          21
+          25
         end
       end
 
@@ -121,13 +121,13 @@
 
     let(:expected_allocations) do
       if RUBY_VERSION < '2.4.0'
-        16
+        20
       elsif RUBY_VERSION < '2.5.0'
-        15
+        19
       elsif RUBY_VERSION < '2.6.0'
-        14
+        18
       else
-        13
+        17
       end
     end
 
@@ -151,13 +151,13 @@
 
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          8
+          12
         elsif RUBY_VERSION < '2.5.0'
-          7
+          11
         elsif RUBY_VERSION < '2.6.0'
-          6
+          10
         else
-          5
+          9
         end
       end
 
@@ -172,13 +172,13 @@
     context 'with tags' do
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          25
+          29
         elsif RUBY_VERSION < '2.5.0'
-          23
+          27
         elsif RUBY_VERSION < '2.6.0'
-          22
+          26
         else
-          21
+          25
         end
       end
 
@@ -200,13 +200,13 @@
 
     let(:expected_allocations) do
       if RUBY_VERSION < '2.4.0'
-        18
+        22
       elsif RUBY_VERSION < '2.5.0'
-        17
+        21
       elsif RUBY_VERSION < '2.6.0'
-        16
+        20
       else
-        15
+        19
       end
     end
 
@@ -230,13 +230,13 @@
 
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          10
+          14
         elsif RUBY_VERSION < '2.5.0'
-          9
+          13
         elsif RUBY_VERSION < '2.6.0'
-          8
+          12
         else
-          7
+          11
         end
       end
 
@@ -251,13 +251,13 @@
     context 'with tags' do
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          27
+          31
         elsif RUBY_VERSION < '2.5.0'
-          25
+          29
         elsif RUBY_VERSION < '2.6.0'
-          24
+          28
         else
-          23
+          27
         end
       end
 
@@ -279,13 +279,13 @@
 
     let(:expected_allocations) do
       if RUBY_VERSION < '2.4.0'
-        14
+        18
       elsif RUBY_VERSION < '2.5.0'
-        13
+        17
       elsif RUBY_VERSION < '2.6.0'
-        12
+        16
       else
-        11
+        15
       end
     end
 
@@ -309,13 +309,13 @@
 
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          6
+          10
         elsif RUBY_VERSION < '2.5.0'
-          5
+          9
         elsif RUBY_VERSION < '2.6.0'
-          4
+          8
         else
-          3
+          7
         end
       end
 
@@ -330,13 +330,13 @@
     context 'with tags' do
       let(:expected_allocations) do
         if RUBY_VERSION < '2.4.0'
-          23
+          27
         elsif RUBY_VERSION < '2.5.0'
-          21
+          25
         elsif RUBY_VERSION < '2.6.0'
-          20
+          24
         else
-          19
+          23
         end
       end
 
@@ -348,4 +348,4 @@
       end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/spec/integrations/buffering_spec.rb b/spec/integrations/buffering_spec.rb
index 4ca72bb4..2b767010 100644
--- a/spec/integrations/buffering_spec.rb
+++ b/spec/integrations/buffering_spec.rb
@@ -141,7 +141,7 @@
     end
 
     let(:buffer_max_pool_size) do
-      9
+      13 # enough messages to include the telemetry 
     end
 
     it 'increments telemetry correctly' do
@@ -156,7 +156,7 @@
 
       subject.flush(flush_telemetry: true, sync: true)
 
-      expect(socket.recv[0]).to eq_with_telemetry('mycounter:1|c', bytes_sent: 702, packets_sent: 1, metrics: 1)
+      expect(socket.recv[0]).to eq_with_telemetry('mycounter:1|c', bytes_sent: 1124, packets_sent: 1, metrics: 1)
 
       subject.increment('myothercounter')
 
@@ -166,7 +166,7 @@
 
       subject.sync_with_outbound_io
 
-      expect(socket.recv[0]).to eq_with_telemetry('myothercounter:1|c', bytes_sent: 687, packets_sent: 1, metrics: 1)
+      expect(socket.recv[0]).to eq_with_telemetry('myothercounter:1|c', bytes_sent: 1110, packets_sent: 1, metrics: 1)
       # last value is still buffered
       expect(socket.recv).to be_nil
     end
@@ -199,7 +199,7 @@
         expect(subject.telemetry.service_checks).to eq 0
         expect(subject.telemetry.events).to eq 0
         expect(subject.telemetry.packets_sent).to eq 1
-        expect(subject.telemetry.bytes_sent).to eq 766
+        expect(subject.telemetry.bytes_sent).to eq 1188
       end
     end
   end
diff --git a/spec/integrations/telemetry_spec.rb b/spec/integrations/telemetry_spec.rb
index 36899143..0ebfa95d 100644
--- a/spec/integrations/telemetry_spec.rb
+++ b/spec/integrations/telemetry_spec.rb
@@ -92,35 +92,35 @@
 
     subject.decrement('test', 1)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('test:-1|c', metrics: 1, packets_sent: 1, bytes_sent: 680)
+    expect(socket.recv[0]).to eq_with_telemetry('test:-1|c', metrics: 1, packets_sent: 1, bytes_sent: 1102)
 
     subject.count('test', 21)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('test:21|c', metrics: 1, packets_sent: 1, bytes_sent: 683)
+    expect(socket.recv[0]).to eq_with_telemetry('test:21|c', metrics: 1, packets_sent: 1, bytes_sent: 1106)
 
     subject.gauge('test', 21)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('test:21|g', metrics: 1, packets_sent: 1, bytes_sent: 683)
+    expect(socket.recv[0]).to eq_with_telemetry('test:21|g', metrics: 1, packets_sent: 1, bytes_sent: 1106)
 
     subject.histogram('test', 21)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('test:21|h', metrics: 1, packets_sent: 1, bytes_sent: 683)
+    expect(socket.recv[0]).to eq_with_telemetry('test:21|h', metrics: 1, packets_sent: 1, bytes_sent: 1106)
 
     subject.timing('test', 21)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('test:21|ms', metrics: 1, packets_sent: 1, bytes_sent: 683)
+    expect(socket.recv[0]).to eq_with_telemetry('test:21|ms', metrics: 1, packets_sent: 1, bytes_sent: 1106)
 
     subject.set('test', 21)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('test:21|s', metrics: 1, packets_sent: 1, bytes_sent: 684)
+    expect(socket.recv[0]).to eq_with_telemetry('test:21|s', metrics: 1, packets_sent: 1, bytes_sent: 1107)
 
     subject.service_check('sc', 0)
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('_sc|sc|0', metrics: 0, service_checks: 1, packets_sent: 1, bytes_sent: 683)
+    expect(socket.recv[0]).to eq_with_telemetry('_sc|sc|0', metrics: 0, service_checks: 1, packets_sent: 1, bytes_sent: 1106)
 
     subject.event('ev', 'text')
     subject.flush(sync: true)
-    expect(socket.recv[0]).to eq_with_telemetry('_e{2,4}:ev|text', metrics: 0, events: 1, packets_sent: 1, bytes_sent: 682)
+    expect(socket.recv[0]).to eq_with_telemetry('_e{2,4}:ev|text', metrics: 0, events: 1, packets_sent: 1, bytes_sent: 1105)
   end
 
   context 'when some data is dropped' do
@@ -139,8 +139,10 @@
       expect(subject.telemetry.events).to eq 0
       expect(subject.telemetry.packets_sent).to eq 0
       expect(subject.telemetry.bytes_sent).to eq 0
-      expect(subject.telemetry.packets_dropped).to eq 1
-      expect(subject.telemetry.bytes_dropped).to eq 1353
+      expect(subject.telemetry.packets_dropped).to eq 2
+      expect(subject.telemetry.packets_dropped_writer).to eq 2
+      expect(subject.telemetry.bytes_dropped).to eq 2196
+      expect(subject.telemetry.bytes_dropped_writer).to eq 2196
 
       subject.gauge('test', 21)
       subject.flush(flush_telemetry: true, sync: true)
@@ -150,23 +152,34 @@
       expect(subject.telemetry.events).to eq 0
       expect(subject.telemetry.packets_sent).to eq 0
       expect(subject.telemetry.bytes_sent).to eq 0
-      expect(subject.telemetry.packets_dropped).to eq 1
-      expect(subject.telemetry.bytes_dropped).to eq 1356
+      expect(subject.telemetry.packets_dropped).to eq 2
+      expect(subject.telemetry.packets_dropped_writer).to eq 2
+      expect(subject.telemetry.bytes_dropped).to eq 2202
+      expect(subject.telemetry.bytes_dropped_writer).to eq 2202
 
       #disable network failure
       socket.error_on_send(nil)
 
       subject.gauge('test', 21)
       subject.flush(sync: true)
-      expect(socket.recv[0]).to eq_with_telemetry('test:21|g', metrics: 1, service_checks: 0, events: 0, packets_dropped: 1, bytes_dropped: 1356)
+      expect(socket.recv[0]).to eq_with_telemetry('test:21|g',
+                                                  metrics: 1,
+                                                  service_checks: 0,
+                                                  events: 0,
+                                                  packets_dropped: 2,
+                                                  packets_dropped_writer: 2,
+                                                  bytes_dropped: 2202,
+                                                  bytes_dropped_writer: 2202)
 
       expect(subject.telemetry.metrics).to eq 0
       expect(subject.telemetry.service_checks).to eq 0
       expect(subject.telemetry.events).to eq 0
       expect(subject.telemetry.packets_sent).to eq 1
-      expect(subject.telemetry.bytes_sent).to eq 684
+      expect(subject.telemetry.bytes_sent).to eq 1109
       expect(subject.telemetry.packets_dropped).to eq 0
+      expect(subject.telemetry.packets_dropped_writer).to eq 0
       expect(subject.telemetry.bytes_dropped).to eq 0
+      expect(subject.telemetry.bytes_dropped_writer).to eq 0
     end
   end
 end
diff --git a/spec/matchers/telemetry_matcher.rb b/spec/matchers/telemetry_matcher.rb
index 3c34e024..55a59509 100644
--- a/spec/matchers/telemetry_matcher.rb
+++ b/spec/matchers/telemetry_matcher.rb
@@ -4,7 +4,19 @@
   telemetry_options ||= {}
 
   # Appends the telemetry metrics to the metrics string passed as 'text'
-  def add_telemetry(text, metrics: 1, events: 0, service_checks: 0, bytes_sent: 0, bytes_dropped:0, packets_sent: 0, packets_dropped: 0, transport: 'udp')
+  def add_telemetry(text,
+                    metrics: 1,
+                    events: 0,
+                    service_checks: 0,
+                    bytes_sent: 0,
+                    bytes_dropped: 0,
+                    bytes_dropped_queue: 0,
+                    bytes_dropped_writer: 0,
+                    packets_sent: 0,
+                    packets_dropped: 0,
+                    packets_dropped_queue: 0,
+                    packets_dropped_writer: 0,
+                    transport: 'udp')
     [
       text,
       "datadog.dogstatsd.client.metrics:#{metrics}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
@@ -12,8 +24,12 @@ def add_telemetry(text, metrics: 1, events: 0, service_checks: 0, bytes_sent: 0,
       "datadog.dogstatsd.client.service_checks:#{service_checks}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
       "datadog.dogstatsd.client.bytes_sent:#{bytes_sent}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
       "datadog.dogstatsd.client.bytes_dropped:#{bytes_dropped}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
+      "datadog.dogstatsd.client.bytes_dropped_queue:#{bytes_dropped_queue}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
+      "datadog.dogstatsd.client.bytes_dropped_writer:#{bytes_dropped_writer}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
       "datadog.dogstatsd.client.packets_sent:#{packets_sent}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
       "datadog.dogstatsd.client.packets_dropped:#{packets_dropped}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
+      "datadog.dogstatsd.client.packets_dropped_queue:#{packets_dropped_queue}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
+      "datadog.dogstatsd.client.packets_dropped_writer:#{packets_dropped_writer}|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:#{transport}",
     ].join("\n")
   end
 
diff --git a/spec/statsd/forwarder_spec.rb b/spec/statsd/forwarder_spec.rb
index aafcdf51..31120824 100644
--- a/spec/statsd/forwarder_spec.rb
+++ b/spec/statsd/forwarder_spec.rb
@@ -109,7 +109,11 @@
       it 'builds the sender' do
         expect(Datadog::Statsd::Sender)
           .to receive(:new)
-          .with(message_buffer, logger: logger, flush_interval: buffer_flush_interval)
+          .with(message_buffer,
+                logger: logger,
+                flush_interval: buffer_flush_interval,
+                queue_size: Datadog::Statsd::UDP_DEFAULT_SENDER_QUEUE_SIZE,
+                telemetry: telemetry)
           .exactly(1)
 
         subject
@@ -288,7 +292,11 @@
       it 'builds the sender' do
         expect(Datadog::Statsd::Sender)
           .to receive(:new)
-          .with(message_buffer, logger: logger, flush_interval: buffer_flush_interval)
+          .with(message_buffer,
+                logger: logger,
+                flush_interval: buffer_flush_interval,
+                queue_size: Datadog::Statsd::UDS_DEFAULT_SENDER_QUEUE_SIZE,
+                telemetry: telemetry)
           .exactly(1)
 
         subject
diff --git a/spec/statsd/sender_spec.rb b/spec/statsd/sender_spec.rb
index 6d35d60c..0ee85bb9 100644
--- a/spec/statsd/sender_spec.rb
+++ b/spec/statsd/sender_spec.rb
@@ -2,14 +2,28 @@
 
 describe Datadog::Statsd::Sender do
   subject do
-    described_class.new(message_buffer, flush_interval: flush_interval)
+    described_class.new(
+      message_buffer,
+      flush_interval: flush_interval,
+      telemetry: telemetry,
+      queue_size: queue_size,
+      queue_class: queue_class,
+      thread_class: thread_class)
   end
 
+  let(:queue_size) { 5 }
+  let(:queue_class) { Queue }
+  let(:thread_class) { Thread }
+
   let(:message_buffer) do
     instance_double(Datadog::Statsd::MessageBuffer)
   end
   let(:flush_interval) { nil }
 
+  let(:telemetry) do
+    instance_double(Datadog::Statsd::Telemetry)
+  end
+
   describe '#start' do
     after do
       subject.stop
@@ -113,7 +127,7 @@
       end
     end
 
-    context 'when starting and stopping' do
+    context 'when started' do
       before do
         subject.start
       end
@@ -131,6 +145,56 @@
 
         subject.rendez_vous
       end
+
+      context 'with fake queue and fake sender thread' do
+        let(:fake_queue) do
+          if Queue.instance_methods.include?(:close)
+            instance_double(Queue, { "length" => fake_queue_length, "<<" => true, "close" => true })
+          else
+            instance_double(Queue, { "length" => fake_queue_length, "<<" => true })
+          end
+        end
+
+        let(:queue_class) do
+          class_double(Queue, new: fake_queue)
+        end
+
+        let(:thread_class) do
+          if Thread.instance_methods.include?(:name=)
+            fake_thread = instance_double(Thread, { "alive?" => true, "name=" => true, "join" => true })
+          else
+            fake_thread = instance_double(Thread, { "alive?" => true, "join" => true })
+          end
+          class_double(Thread, new: fake_thread)
+        end
+
+        context 'with fewer messages in queue than queue_size' do
+          let(:fake_queue_length) { queue_size }
+
+          it 'adds only messages up to queue_size messages' do
+            expect(fake_queue).to receive(:<<).with('message')
+            if not Queue.instance_methods.include?(:close)
+              expect(fake_queue).to receive(:<<).with(:close)
+            end
+            expect(telemetry).not_to receive(:dropped_queue)
+            subject.add('message')
+          end
+        end
+
+        context 'with more messages in queue than queue_size' do
+          let(:fake_queue_length) { queue_size + 1 }
+
+          it 'adds only messages up to queue_size messages' do
+            if Queue.instance_methods.include?(:close)
+              expect(fake_queue).not_to receive(:<<)
+            else
+              expect(fake_queue).to receive(:<<).with(:close)
+            end
+            expect(telemetry).to receive(:dropped_queue).with(bytes: 7, packets: 1)
+            subject.add('message')
+          end
+        end
+      end
     end
   end
 
diff --git a/spec/statsd/telemetry_spec.rb b/spec/statsd/telemetry_spec.rb
index faab9deb..55f21e58 100644
--- a/spec/statsd/telemetry_spec.rb
+++ b/spec/statsd/telemetry_spec.rb
@@ -77,7 +77,8 @@
   describe '#flush' do
     before do
       subject.sent(metrics: 1, events: 2, service_checks: 3, bytes: 4, packets: 5)
-      subject.dropped(bytes: 6, packets: 7)
+      subject.dropped_writer(bytes: 6, packets: 7)
+      subject.dropped_queue(bytes: 9, packets: 8)
       subject.flush
     end
 
@@ -87,22 +88,21 @@
         "datadog.dogstatsd.client.events:2|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
         "datadog.dogstatsd.client.service_checks:3|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
         "datadog.dogstatsd.client.bytes_sent:4|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
-        "datadog.dogstatsd.client.bytes_dropped:6|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
+        "datadog.dogstatsd.client.bytes_dropped:15|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
+        "datadog.dogstatsd.client.bytes_dropped_queue:9|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
+        "datadog.dogstatsd.client.bytes_dropped_writer:6|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
         "datadog.dogstatsd.client.packets_sent:5|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
-        "datadog.dogstatsd.client.packets_dropped:7|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
+        "datadog.dogstatsd.client.packets_dropped:15|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
+        "datadog.dogstatsd.client.packets_dropped_queue:8|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
+        "datadog.dogstatsd.client.packets_dropped_writer:7|c|#client:ruby,client_version:#{Datadog::Statsd::VERSION},client_transport:doe",
       ]
     end
 
-    context do
-      before do
-        skip 'Ruby too old' if RUBY_VERSION < '2.3.0'
-      end
-
-      it 'makes only 8 allocations' do
-        expect do
-          subject.flush
-        end.to make_allocations(8)
-      end
+    it do
+      skip 'Ruby too old' if RUBY_VERSION < '2.3.0'
+      expect do
+        subject.flush
+      end.to make_allocations(12)
     end
   end
 
@@ -112,7 +112,8 @@
       allow(Process).to receive(:clock_gettime).and_return(0) if Datadog::Statsd::PROCESS_TIME_SUPPORTED
 
       subject.sent(metrics: 1, events: 2, service_checks: 3, bytes: 4, packets: 5)
-      subject.dropped(bytes: 6, packets: 7)
+      subject.dropped_writer(bytes: 6, packets: 7)
+      subject.dropped_queue(bytes: 9, packets: 7)
     end
 
     after do
@@ -161,13 +162,37 @@
     it 'resets the bytes_dropped' do
       expect do
         subject.reset
-      end.to change { subject.bytes_dropped }.from(6).to(0)
+      end.to change { subject.bytes_dropped}.from(15).to(0)
+    end
+
+    it 'resets the bytes_dropped_queue' do
+      expect do
+        subject.reset
+      end.to change { subject.bytes_dropped_queue }.from(9).to(0)
+    end
+
+    it 'resets the bytes_dropped_writer' do
+      expect do
+        subject.reset
+      end.to change { subject.bytes_dropped_writer }.from(6).to(0)
     end
 
     it 'resets the packets_dropped' do
       expect do
         subject.reset
-      end.to change { subject.packets_dropped }.from(7).to(0)
+      end.to change { subject.packets_dropped}.from(14).to(0)
+    end
+
+    it 'resets the packets_dropped_queue' do
+      expect do
+        subject.reset
+      end.to change { subject.packets_dropped_queue }.from(7).to(0)
+    end
+
+    it 'resets the packets_dropped_writer' do
+      expect do
+        subject.reset
+      end.to change { subject.packets_dropped_writer }.from(7).to(0)
     end
   end
 
@@ -213,19 +238,61 @@
     end
   end
 
-  describe '#dropped' do
+  describe '#dropped_queue' do
     context 'when bumping bytes' do
+      it 'has bumped bytes_dropped_queue by the right amount' do
+        expect do
+          subject.dropped_queue(bytes: 3)
+        end.to change { subject.bytes_dropped_queue }.from(0).to(3)
+      end
+
       it 'has bumped bytes_dropped by the right amount' do
         expect do
-          subject.dropped(bytes: 3)
+          subject.dropped_queue(bytes: 3)
         end.to change { subject.bytes_dropped }.from(0).to(3)
       end
     end
 
     context 'when bumping packets' do
+      it 'has bumped packets_dropped_queue by the right amount' do
+        expect do
+          subject.dropped_queue(packets: 3)
+        end.to change { subject.packets_dropped_queue }.from(0).to(3)
+      end
+
+      it 'has bumped packets_dropped by the right amount' do
+        expect do
+          subject.dropped_queue(packets: 3)
+        end.to change { subject.packets_dropped }.from(0).to(3)
+      end
+    end
+  end
+
+  describe '#dropped_writer' do
+    context 'when bumping bytes' do
+      it 'has bumped bytes_dropped_writer by the right amount' do
+        expect do
+          subject.dropped_writer(bytes: 3)
+        end.to change { subject.bytes_dropped_writer }.from(0).to(3)
+      end
+
+      it 'has bumped bytes_dropped by the right amount' do
+        expect do
+          subject.dropped_writer(bytes: 3)
+        end.to change { subject.bytes_dropped }.from(0).to(3)
+      end
+    end
+
+    context 'when bumping packets' do
+      it 'has bumped packets_dropped_writer by the right amount' do
+        expect do
+          subject.dropped_writer(packets: 3)
+        end.to change { subject.packets_dropped_writer }.from(0).to(3)
+      end
+
       it 'has bumped packets_dropped by the right amount' do
         expect do
-          subject.dropped(packets: 3)
+          subject.dropped_writer(packets: 3)
         end.to change { subject.packets_dropped }.from(0).to(3)
       end
     end
diff --git a/spec/statsd/udp_connection_spec.rb b/spec/statsd/udp_connection_spec.rb
index 66baeac4..3c9d6e2a 100644
--- a/spec/statsd/udp_connection_spec.rb
+++ b/spec/statsd/udp_connection_spec.rb
@@ -51,7 +51,7 @@
 
   describe '#write' do
     let(:telemetry) do
-      instance_double(Datadog::Statsd::Telemetry, sent: true, dropped: true)
+      instance_double(Datadog::Statsd::Telemetry, sent: true, dropped_writer: true)
     end
 
     it 'connects to the right host and port' do
@@ -108,9 +108,9 @@
           subject.write('test')
         end
 
-        it 'updates the "dropped" telemetry counts' do
+        it 'updates the "dropped_writer" telemetry counts' do
           expect(telemetry)
-            .to receive(:dropped)
+            .to receive(:dropped_writer)
             .with(bytes: 4, packets: 1)
 
           subject.write('test')
@@ -262,9 +262,9 @@
               subject.write('test')
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -289,9 +289,9 @@
               expect(log.string).to match 'Statsd: SocketError yolo'
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -336,9 +336,9 @@
               subject.write('test')
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -463,9 +463,9 @@
               subject.write('test')
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -528,9 +528,9 @@
               subject.write('test')
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
diff --git a/spec/statsd/uds_connection_spec.rb b/spec/statsd/uds_connection_spec.rb
index fa7695b4..b8814cfe 100644
--- a/spec/statsd/uds_connection_spec.rb
+++ b/spec/statsd/uds_connection_spec.rb
@@ -42,7 +42,7 @@
 
   describe '#write' do
     let(:telemetry) do
-      instance_double(Datadog::Statsd::Telemetry, sent: true, dropped: true)
+      instance_double(Datadog::Statsd::Telemetry, sent: true, dropped_writer: true)
     end
 
     it 'builds the socket in the right mode' do
@@ -142,9 +142,9 @@
             expect(log.string).to match 'Statsd: Datadog::Statsd::UDSConnection::BadSocketError Errno::ECONNRESET: Connection reset by peer'
           end
 
-          it 'updates the "dropped" telemetry counts' do
+          it 'updates the "dropped_writer" telemetry counts' do
             expect(telemetry)
-              .to receive(:dropped)
+              .to receive(:dropped_writer)
               .with(bytes: 4, packets: 1)
 
             subject.write('test')
@@ -171,9 +171,9 @@
               expect(log.string).to match 'Statsd: RuntimeError yolo'
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -199,9 +199,9 @@
               expect(log.string).to match 'Statsd: SocketError yolo'
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -248,9 +248,9 @@
             expect(log.string).to match 'Statsd: Datadog::Statsd::UDSConnection::BadSocketError Errno::ECONNREFUSED: Connection refused - closed stream'
           end
 
-          it 'updates the "dropped" telemetry counts' do
+          it 'updates the "dropped_writer" telemetry counts' do
             expect(telemetry)
-              .to receive(:dropped)
+              .to receive(:dropped_writer)
               .with(bytes: 4, packets: 1)
 
             subject.write('test')
@@ -277,9 +277,9 @@
               expect(log.string).to match 'Statsd: RuntimeError yolo'
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -305,9 +305,9 @@
               expect(log.string).to match 'Errno::ECONNREFUSED Connection refused - yolo'
             end
 
-            it 'updates the "dropped" telemetry counts' do
+            it 'updates the "dropped_writer" telemetry counts' do
               expect(telemetry)
-                .to receive(:dropped)
+                .to receive(:dropped_writer)
                 .with(bytes: 4, packets: 1)
 
               subject.write('test')
@@ -351,9 +351,9 @@
           expect(log.string).to match 'Statsd: Errno::ENOENT No such file or directory'
         end
 
-        it 'updates the "dropped" telemetry counts' do
+        it 'updates the "dropped_writer" telemetry counts' do
           expect(telemetry)
-            .to receive(:dropped)
+            .to receive(:dropped_writer)
             .with(bytes: 4, packets: 1)
 
           subject.write('test')
@@ -398,9 +398,9 @@
           expect(log.string).to match 'Statsd: IO::EAGAINWaitWritable Resource temporarily unavailable'
         end
 
-        it 'updates the "dropped" telemetry counts' do
+        it 'updates the "dropped_writer" telemetry counts' do
           expect(telemetry)
-            .to receive(:dropped)
+            .to receive(:dropped_writer)
             .with(bytes: 4, packets: 1)
 
           subject.write('test')
diff --git a/spec/statsd_spec.rb b/spec/statsd_spec.rb
index bdbf8fb2..64d87a8c 100644
--- a/spec/statsd_spec.rb
+++ b/spec/statsd_spec.rb
@@ -397,7 +397,7 @@
       subject.gauge('begrutten-suffusion', -107.3)
       subject.flush(sync: true)
 
-      expect(socket.recv[0]).to eq_with_telemetry 'begrutten-suffusion:-107.3|g', bytes_sent: 697, packets_sent: 1
+      expect(socket.recv[0]).to eq_with_telemetry 'begrutten-suffusion:-107.3|g', bytes_sent: 1119, packets_sent: 1
     end
 
     context 'with a sample rate' do
@@ -455,7 +455,7 @@
       subject.histogram('ohmy', -107.3)
       subject.flush(sync: true)
 
-      expect(socket.recv[0]).to eq_with_telemetry 'ohmy:-107.3|h', bytes_sent: 682, packets_sent: 1
+      expect(socket.recv[0]).to eq_with_telemetry 'ohmy:-107.3|h', bytes_sent: 1104, packets_sent: 1
     end
 
     context 'with a sample rate' do