diff --git a/NLog.Web.AspNetCore.Tests/LayoutRenderers/AspNetQueryStringLayoutRendererTests.cs b/NLog.Web.AspNetCore.Tests/LayoutRenderers/AspNetQueryStringLayoutRendererTests.cs
index 80b3f992..7283072c 100644
--- a/NLog.Web.AspNetCore.Tests/LayoutRenderers/AspNetQueryStringLayoutRendererTests.cs
+++ b/NLog.Web.AspNetCore.Tests/LayoutRenderers/AspNetQueryStringLayoutRendererTests.cs
@@ -1,5 +1,4 @@
-#if !NETSTANDARD_1plus
-//todo nsubstitute
+
 
 using System;
 using System.Collections.Generic;
@@ -13,70 +12,23 @@
 using Microsoft.Extensions.Primitives;
 using HttpContextBase = Microsoft.AspNetCore.Http.HttpContext;
 using HttpSessionState = Microsoft.AspNetCore.Http.ISession;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Internal;
 #endif
 using NLog.Web.LayoutRenderers;
 using NSubstitute;
 using NLog.Web.Enums;
 using Xunit;
-using System.Collections.Specialized;
-using System.Reflection;
-using NLog.Targets;
-using NLog.Layouts;
+
 
 namespace NLog.Web.Tests.LayoutRenderers
 {
     public class AspNetQueryStringLayoutRendererTests : TestInvolvingAspNetHttpContext
     {
-        public AspNetQueryStringLayoutRendererTests() : base()
-        {
-            this.SetUp();
-        }
-
-        public void SetUp()
-        {
-            //auto load won't work yet (in DNX), so use <extensions>            
-            SetupFakeSession();
-        }
-
-        protected override void CleanUp()
-        {
-            Session.Clear();
-        }
-
-        private HttpSessionState Session
-        {
-            get
-            {
-#if NETSTANDARD_1plus
-                return HttpContext.Session;
-#else
-                return HttpContext.Current.Session;
-#endif
-            }
-        }
-
-        public void SetupFakeSession()
-        {
-            var sessionContainer = new HttpSessionStateContainer("id", new SessionStateItemCollection(),
-                                                    new HttpStaticObjectsCollection(), 10, true,
-                                                    HttpCookieMode.AutoDetect,
-                                                    SessionStateMode.InProc, false);
-
-            HttpContext.Items["AspSession"] = typeof(HttpSessionState).GetConstructor(
-                                        BindingFlags.NonPublic | BindingFlags.Instance,
-                                        null, CallingConventions.Standard,
-                                        new[] { typeof(HttpSessionStateContainer) },
-                                        null)
-                                .Invoke(new object[] { sessionContainer });
-        }
-
         [Fact]
         public void NullKeyRendersEmptyString()
         {
-            var httpContext = Substitute.For<HttpContextBase>();
-
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+            var renderer = CreateAndMockRenderer();
             renderer.QueryStringKeys = null;
 
             string result = renderer.Render(new LogEventInfo());
@@ -87,13 +39,8 @@ public void NullKeyRendersEmptyString()
         [Fact]
         public void KeyNotFoundRendersEmptyString_Flat_Formatting()
         {
-            var httpContext = Substitute.For<HttpContextBase>();
-            var namedClollection = new NameValueCollection();
-            namedClollection.Add("Id", "1");
-            httpContext.Request.QueryString.Returns(namedClollection);
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"));
 
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
             renderer.QueryStringKeys = new List<string> { "key" };
             renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Flat;
 
@@ -105,13 +52,8 @@ public void KeyNotFoundRendersEmptyString_Flat_Formatting()
         [Fact]
         public void KeyNotFoundRendersEmptyString_Json_Formatting()
         {
-            var httpContext = Substitute.For<HttpContextBase>();
-            var namedClollection = new NameValueCollection();
-            namedClollection.Add("Id", "1");
-            httpContext.Request.QueryString.Returns(namedClollection);
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"));
 
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
             renderer.QueryStringKeys = new List<string> { "key" };
             renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Json;
 
@@ -120,17 +62,16 @@ public void KeyNotFoundRendersEmptyString_Json_Formatting()
             Assert.Empty(result);
         }
 
+
+
+
         [Fact]
         public void KeyFoundRendersValue_QueryString_Single_Item_Flat_Formatting()
         {
             var expectedResult = "Id:1";
-            var httpContext = Substitute.For<HttpContextBase>();
-            var namedClollection = new NameValueCollection();
-            namedClollection.Add("Id", "1");
-            httpContext.Request.QueryString.Returns(namedClollection);
 
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"));
+
             renderer.QueryStringKeys = new List<string> { "Id" };
             renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Flat;
 
@@ -143,13 +84,9 @@ public void KeyFoundRendersValue_QueryString_Single_Item_Flat_Formatting()
         public void KeyFoundRendersValue_QueryString_Single_Item_Json_Formatting()
         {
             var expectedResult = "[{\"Id\":\"1\"}]";
-            var httpContext = Substitute.For<HttpContextBase>();
-            var namedClollection = new NameValueCollection();
-            namedClollection.Add("Id", "1");
-            httpContext.Request.QueryString.Returns(namedClollection);
 
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"));
+
             renderer.QueryStringKeys = new List<string> { "Id" };
             renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Json;
 
@@ -162,14 +99,9 @@ public void KeyFoundRendersValue_QueryString_Single_Item_Json_Formatting()
         public void KeyFoundRendersValue_QueryString_Multiple_Item_Flat_Formatting()
         {
             var expectedResult = "Id:1," + Environment.NewLine + "Id2:2";
-            var httpContext = Substitute.For<HttpContextBase>();
-            var namedClollection = new NameValueCollection();
-            namedClollection.Add("Id", "1");
-            namedClollection.Add("Id2", "2");
-            httpContext.Request.QueryString.Returns(namedClollection);
 
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"), CreateTuple("Id2", "2"));
+
             renderer.QueryStringKeys = new List<string> { "Id", "Id2" };
             renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Flat;
 
@@ -178,25 +110,119 @@ public void KeyFoundRendersValue_QueryString_Multiple_Item_Flat_Formatting()
             Assert.Equal(expectedResult, result);
         }
 
+        [Fact]
+        public void EmptyProperyShouldListAll()
+        {
+            var expectedResult = "Id:1," + Environment.NewLine + "Id2:2";
+
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"), CreateTuple("Id2", "2"));
+
+            renderer.QueryStringKeys = new List<string> { };
+            renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Flat;
+
+            string result = renderer.Render(new LogEventInfo());
+
+            Assert.Equal(expectedResult, result);
+        }
+
+        [Fact]
+        public void NullProperyShouldListAll()
+        {
+            var expectedResult = "Id:1," + Environment.NewLine + "Id2:2";
+
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"), CreateTuple("Id2", "2"));
+
+            renderer.QueryStringKeys = null;
+            renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Flat;
+
+            string result = renderer.Render(new LogEventInfo());
+
+            Assert.Equal(expectedResult, result);
+        }
+        [Fact]
+        public void MultipleValuesForOneKeyShouldWork()
+        {
+            var expectedResult = "Id:1,2,3";
+
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1", "2", "3"));
+
+            renderer.QueryStringKeys = null;
+            renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Flat;
+
+            string result = renderer.Render(new LogEventInfo());
+
+            Assert.Equal(expectedResult, result);
+        }
+
         [Fact]
         public void KeyFoundRendersValue_QueryString_Multiple_Item_Json_Formatting()
         {
             var expectedResult = "[" + "{\"Id\":\"1\"}," + Environment.NewLine + "{\"Id2\":\"2\"}" + "]";
-            var httpContext = Substitute.For<HttpContextBase>();
-            var namedClollection = new NameValueCollection();
-            namedClollection.Add("Id", "1");
-            namedClollection.Add("Id2", "2");
-            httpContext.Request.QueryString.Returns(namedClollection);
 
-            var renderer = new AspNetQueryStringLayoutRenderer();
-            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+            var renderer = CreateAndMockRenderer(CreateTuple("Id", "1"), CreateTuple("Id2", "2"));
+
             renderer.QueryStringKeys = new List<string> { "Id", "Id2" };
             renderer.OutputFormat = AspNetRequestLayoutOutputFormat.Json;
 
             string result = renderer.Render(new LogEventInfo());
 
             Assert.Equal(expectedResult, result);
-        }       
+        }
+
+    
+        /// <summary>
+        /// Create tuple with 1 or more values (with 1 key)
+        /// </summary>
+        /// <param name="key"></param>
+        /// <param name="values"></param>
+        /// <returns></returns>
+        private static Tuple<string, string[]> CreateTuple(string key, params string[] values)
+        {
+            return new Tuple<string, string[]>(key, values);
+        }
+
+
+        private static AspNetQueryStringLayoutRenderer CreateAndMockRenderer(params Tuple<string, string[]>[] values)
+        {
+            var renderer = new AspNetQueryStringLayoutRenderer();
+
+#if !NETSTANDARD_1plus
+
+            var httpContext = Substitute.For<HttpContextBase>();
+            var namedClollection = new NameValueCollection();
+            foreach (var tuple in values)
+            {
+                foreach (var value in tuple.Item2)
+                {
+                    namedClollection.Add(tuple.Item1, value);
+                }
+
+            }
+
+            httpContext.Request.QueryString.Returns(namedClollection);
+
+            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+#else
+            var httpContext = Substitute.For<HttpContextBase>();
+            var dict = new Dictionary<string, StringValues>();
+            foreach (var tuple in values)
+            {
+                dict.Add(tuple.Item1, new StringValues(tuple.Item2));
+
+            }
+            IQueryCollection querystringValues = new QueryCollection(dict);
+
+            httpContext.Request.Query.Returns(querystringValues);
+
+            renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+#endif
+
+            return renderer;
+
+
+
+        }
+
+
     }
 }
-#endif
\ No newline at end of file
diff --git a/NLog.Web.AspNetCore/LayoutRenderers/AspNetRequestQueryStringLayoutRenderer.cs b/NLog.Web.AspNetCore/LayoutRenderers/AspNetRequestQueryStringLayoutRenderer.cs
index 67fe127c..46ea41e5 100644
--- a/NLog.Web.AspNetCore/LayoutRenderers/AspNetRequestQueryStringLayoutRenderer.cs
+++ b/NLog.Web.AspNetCore/LayoutRenderers/AspNetRequestQueryStringLayoutRenderer.cs
@@ -10,6 +10,7 @@
 using NLog.Config;
 using NLog.Web.Enums;
 using System;
+using System.Linq;
 using NLog.Web.Internal;
 
 namespace NLog.Web.LayoutRenderers
@@ -29,6 +30,7 @@ public class AspNetQueryStringLayoutRenderer : AspNetLayoutRendererBase
     {
         /// <summary>
         /// List Query Strings' Key to be rendered from Request.
+        /// If empty, then render all querystrings
         /// </summary>
         public List<String> QueryStringKeys { get; set; }
 
@@ -46,41 +48,70 @@ public class AspNetQueryStringLayoutRenderer : AspNetLayoutRendererBase
         protected override void DoAppend(StringBuilder builder, LogEventInfo logEvent)
         {
             var httpRequest = HttpContextAccessor?.HttpContext?.TryGetRequest();
+            if (httpRequest == null)
+                return;
 
-            if (this.QueryStringKeys?.Count > 0)
-            {
-                if (httpRequest == null)
-                    return;
-
-                var includeArrayEndBraces = false;
-                var firstItem = true;
+ 
 
+           
+            var allQueryStrings = this.QueryStringKeys == null || this.QueryStringKeys.Count == 0;
+            var queryStringKeys = this.QueryStringKeys;
 #if !NETSTANDARD_1plus
-                var queryStrings = httpRequest.QueryString;
+            var queryStrings = httpRequest.QueryString;
+
+            if (queryStrings == null)
+                return;
+
+
+            if (allQueryStrings)
+            {
+                queryStringKeys = new List<string>(queryStrings.Keys.Count);
+
+                foreach (var key in queryStrings.Keys)
+                {
+                    if (key != null)
+                    {
+                        queryStringKeys.Add(key.ToString());
+                    }
+                }
+            }
 #else
-                var queryStrings = httpRequest.Query;
+            var queryStrings = httpRequest.Query;
+
+            if (queryStrings == null)
+                return;
+
+            if (allQueryStrings)
+            {
+                queryStringKeys = queryStrings.Keys.ToList();
+            }
 #endif
-                if (queryStrings?.Count > 0)
+
+
+            var includeArrayEndBraces = false;
+            
+            if (queryStrings.Count > 0)
+            {
+                var firstItem = true;
+
+                foreach (var configuredKey in queryStringKeys)
                 {
-                    foreach (var configuredKey in this.QueryStringKeys)
-                    {
-                        // This platoform specific code is to prevent an unncessary .ToString call otherwise. 
+                    // This platoform specific code is to prevent an unncessary .ToString call otherwise. 
 #if !NETSTANDARD_1plus
-                        var value = queryStrings[configuredKey];
+                    var value = queryStrings[configuredKey];
 #else
-                        var value = queryStrings[configuredKey].ToString();
+                    var value = queryStrings[configuredKey].ToString();
 #endif
-                        if (!String.IsNullOrEmpty(value))
-                        {
-                            this.AppendKeyAndValue(builder, configuredKey, value, firstItem, ref includeArrayEndBraces);
-                            firstItem = false;
-                        }
+                    if (!String.IsNullOrEmpty(value))
+                    {
+                        this.AppendKeyAndValue(builder, configuredKey, value, firstItem, ref includeArrayEndBraces);
+                        firstItem = false;
                     }
                 }
-
-                if (includeArrayEndBraces)
-                    builder.Append(GlobalConstants.jsonArrayEndBraces);
             }
+
+            if (includeArrayEndBraces)
+                builder.Append(GlobalConstants.jsonArrayEndBraces);
         }
 
         /// <summary>