diff --git a/tests/unit/test_filters.py b/tests/unit/test_filters.py
index 07c39944a8bc..261e224eb887 100644
--- a/tests/unit/test_filters.py
+++ b/tests/unit/test_filters.py
@@ -35,12 +35,9 @@ def test_camo_url():
 
 class TestReadmeRender:
 
-    def test_can_render(self, monkeypatch):
-        monkeypatch.setattr(
-            readme_renderer.rst,
-            "render",
-            lambda raw: "rendered",
-        )
+    def test_can_render_rst(self, monkeypatch):
+        renderer = pretend.call_recorder(lambda raw: "rendered")
+        monkeypatch.setattr(readme_renderer.rst, "render", renderer)
 
         ctx = {
             "request": pretend.stub(
@@ -53,15 +50,18 @@ def test_can_render(self, monkeypatch):
             ),
         }
 
-        result = filters.readme(ctx, "raw thing", format="rst")
+        result = filters.readme(
+            ctx, "raw thing", description_content_type="text/x-rst",
+        )
 
         assert result == jinja2.Markup("rendered")
+        assert renderer.calls == [pretend.call('raw thing')]
 
-    def test_cant_render(self, monkeypatch):
-        monkeypatch.setattr(readme_renderer.rst, "render", lambda raw: None)
-        monkeypatch.setattr(
-            readme_renderer.txt, "render", lambda raw: "rendered<br>thing",
-        )
+    def test_cant_render_rst(self, monkeypatch):
+        rst_renderer = pretend.call_recorder(lambda raw: None)
+        txt_renderer = pretend.call_recorder(lambda raw: "rendered<br>thing")
+        monkeypatch.setattr(readme_renderer.rst, "render", rst_renderer)
+        monkeypatch.setattr(readme_renderer.txt, "render", txt_renderer)
 
         ctx = {
             "request": pretend.stub(
@@ -74,9 +74,57 @@ def test_cant_render(self, monkeypatch):
             ),
         }
 
-        result = filters.readme(ctx, "raw thing", format="rst")
+        result = filters.readme(
+            ctx, "raw thing", description_content_type="text/x-rst",
+        )
 
         assert result == jinja2.Markup("rendered<br>thing")
+        assert rst_renderer.calls == [pretend.call('raw thing')]
+        assert txt_renderer.calls == [pretend.call('raw thing')]
+
+    def test_can_render_plaintext(self, monkeypatch):
+        renderer = pretend.call_recorder(lambda raw: "rendered")
+        monkeypatch.setattr(readme_renderer.txt, "render", renderer)
+
+        ctx = {
+            "request": pretend.stub(
+                registry=pretend.stub(
+                    settings={
+                        "camo.url": "https://camo.example.net/",
+                        "camo.key": "fake key",
+                    },
+                ),
+            ),
+        }
+
+        result = filters.readme(
+            ctx, "raw thing", description_content_type="text/plain",
+        )
+
+        assert result == jinja2.Markup("rendered")
+        assert renderer.calls == [pretend.call('raw thing')]
+
+    def test_can_render_markdown(self, monkeypatch):
+        renderer = pretend.call_recorder(lambda raw: "rendered")
+        monkeypatch.setattr(readme_renderer.markdown, "render", renderer)
+
+        ctx = {
+            "request": pretend.stub(
+                registry=pretend.stub(
+                    settings={
+                        "camo.url": "https://camo.example.net/",
+                        "camo.key": "fake key",
+                    },
+                ),
+            ),
+        }
+
+        result = filters.readme(
+            ctx, "raw thing", description_content_type="text/markdown",
+        )
+
+        assert result == jinja2.Markup("rendered")
+        assert renderer.calls == [pretend.call('raw thing')]
 
     def test_renders_camo(self, monkeypatch):
         html = "<img src=http://example.com/image.jpg>"
@@ -98,7 +146,9 @@ def test_renders_camo(self, monkeypatch):
             ),
         }
 
-        result = filters.readme(ctx, "raw thing", format="rst")
+        result = filters.readme(
+            ctx, "raw thing", description_content_type="text/x-rst",
+        )
 
         assert result == jinja2.Markup(
             '<img src="https://camo.example.net/image.jpg">'
@@ -131,7 +181,9 @@ def test_renders_camo_no_src(self, monkeypatch):
             ),
         }
 
-        result = filters.readme(ctx, "raw thing", format="rst")
+        result = filters.readme(
+            ctx, "raw thing", description_content_type="text/x-rst",
+        )
 
         assert result == jinja2.Markup("<img>")
         assert gen_camo_url.calls == []
diff --git a/warehouse/filters.py b/warehouse/filters.py
index c0cd4b0d976e..040bf8bdd2c8 100644
--- a/warehouse/filters.py
+++ b/warehouse/filters.py
@@ -11,6 +11,7 @@
 # limitations under the License.
 
 import binascii
+import cgi
 import collections
 import enum
 import hmac
@@ -24,6 +25,7 @@
 import jinja2
 
 import packaging.version
+import readme_renderer.markdown
 import readme_renderer.rst
 import readme_renderer.txt
 
@@ -31,6 +33,13 @@
 
 from warehouse.utils.http import is_valid_uri
 
+_renderers = {
+    '': readme_renderer.rst,  # Default if description_content_type is None
+    'text/plain': readme_renderer.txt,
+    'text/x-rst': readme_renderer.rst,
+    'text/markdown': readme_renderer.markdown,
+}
+
 
 class PackageType(enum.Enum):
     bdist_dmg = "OSX Disk Image"
@@ -63,23 +72,22 @@ def _camo_url(camo_url, camo_key, url):
 
 
 @jinja2.contextfilter
-def readme(ctx, value, *, format):
+def readme(ctx, value, *, description_content_type):
     request = ctx.get("request") or get_current_request()
 
     camo_url = request.registry.settings["camo.url"].format(request=request)
     camo_key = request.registry.settings["camo.key"]
 
-    # The format parameter is here so we can more easily expand this to cover
-    # READMEs which do not use restructuredtext, but for now rst is the only
-    # format we support.
-    assert format == "rst", "We currently only support rst rendering."
+    content_type, parameters = cgi.parse_header(description_content_type)
+
+    # Get the appropriate renderer
+    renderer = _renderers[content_type]
 
     # Actually render the given value, this will not only render the value, but
     # also ensure that it's had any disallowed markup removed.
-    rendered = readme_renderer.rst.render(value)
+    rendered = renderer.render(value, **parameters)
 
-    # If the content was not rendered, we'll replace the newlines with breaks
-    # so that it shows up nicer when rendered.
+    # If the content was not rendered, we'll render as plaintext instead
     if rendered is None:
         rendered = readme_renderer.txt.render(value)
 
diff --git a/warehouse/templates/packaging/detail.html b/warehouse/templates/packaging/detail.html
index c6d89588ffa8..e389d4d180ca 100644
--- a/warehouse/templates/packaging/detail.html
+++ b/warehouse/templates/packaging/detail.html
@@ -234,7 +234,7 @@ <h3>Classifiers</h3>
           <h2 class="page-title">Project Description</h2>
           {% if release.description %}
           <div class="project-description">
-            {{ release.description|readme(format="rst") }}
+            {{ release.description|readme(description_content_type=release.description_content_type) }}
           </div>
           {% else %}
           <div class="callout-block">