diff --git a/src/OpenTracing/Noop/NoopScopeManager.cs b/src/OpenTracing/Noop/NoopScopeManager.cs
index 5d627f0..343c5f4 100644
--- a/src/OpenTracing/Noop/NoopScopeManager.cs
+++ b/src/OpenTracing/Noop/NoopScopeManager.cs
@@ -7,7 +7,7 @@ internal sealed class NoopScopeManager : IScopeManager
     {
         internal static readonly NoopScopeManager Instance = new NoopScopeManager();
 
-        public IScope Active => null;
+        public IScope Active => NoopScope.Instance;
 
         private NoopScopeManager()
         {
diff --git a/src/OpenTracing/Noop/NoopTracer.cs b/src/OpenTracing/Noop/NoopTracer.cs
index 6d4bde1..1546935 100644
--- a/src/OpenTracing/Noop/NoopTracer.cs
+++ b/src/OpenTracing/Noop/NoopTracer.cs
@@ -8,7 +8,7 @@ internal sealed class NoopTracer : ITracer
 
         public IScopeManager ScopeManager => NoopScopeManager.Instance;
 
-        public ISpan ActiveSpan => null;
+        public ISpan ActiveSpan => NoopSpan.Instance;
 
         private NoopTracer()
         {
diff --git a/test/OpenTracing.Tests/Noop/NoopScopeManagerTests.cs b/test/OpenTracing.Tests/Noop/NoopScopeManagerTests.cs
new file mode 100644
index 0000000..ead0c85
--- /dev/null
+++ b/test/OpenTracing.Tests/Noop/NoopScopeManagerTests.cs
@@ -0,0 +1,17 @@
+using OpenTracing.Noop;
+using Xunit;
+
+namespace OpenTracing.Tests.Noop
+{
+    public class NoopScopeManagerTests
+    {
+
+        [Fact]
+        public void ActiveValueToleratesUse()
+        {
+            IScope active = NoopScopeManager.Instance.Active;
+            Assert.NotNull(active);
+            active.Dispose();
+        }
+    }
+}
diff --git a/test/OpenTracing.Tests/Noop/NoopTests.cs b/test/OpenTracing.Tests/Noop/NoopTests.cs
index 566f839..5482da0 100644
--- a/test/OpenTracing.Tests/Noop/NoopTests.cs
+++ b/test/OpenTracing.Tests/Noop/NoopTests.cs
@@ -21,15 +21,16 @@ public void Tracer_uses_NoopScopeManager()
         {
             var tracer = NoopTracerFactory.Create();
 
-            Assert.IsType<NoopScopeManager>(tracer.ScopeManager);
+            Assert.Same(NoopScopeManager.Instance, tracer.ScopeManager);
         }
 
         [Fact]
-        public void Tracer_initially_has_no_active_span()
+        public void Tracer_ActiveSpan_is_NoopSpan()
         {
             var tracer = NoopTracerFactory.Create();
 
-            Assert.Null(tracer.ActiveSpan);
+            var span = tracer.ActiveSpan;
+            Assert.Same(NoopSpan.Instance, span);
         }
 
         [Fact]
@@ -39,7 +40,7 @@ public void BuildSpan_returns_NoopSpanBuilder()
 
             var spanBuilder = tracer.BuildSpan("noop");
 
-            Assert.IsType<NoopSpanBuilder>(spanBuilder);
+            Assert.Same(NoopSpanBuilder.Instance, spanBuilder);
         }
 
         [Fact]
@@ -61,7 +62,7 @@ public void StartActive_returns_NoopScope()
             var scope = tracer.BuildSpan("noop")
                 .StartActive(finishSpanOnDispose: false);
 
-            Assert.IsType<NoopScopeManager.NoopScope>(scope);
+            Assert.Same(NoopScopeManager.NoopScope.Instance, scope);
         }
 
         [Fact]
@@ -72,29 +73,29 @@ public void NoopScope_from_StartActive_has_NoopSpan()
             var scope = tracer.BuildSpan("noop")
                 .StartActive(finishSpanOnDispose: false);
 
-            Assert.IsType<NoopSpan>(scope.Span);
+            Assert.Same(NoopSpan.Instance, scope.Span);
         }
 
         [Fact]
-        public void StartActive_does_NOT_set_Tracer_ActiveSpan()
+        public void StartActive_sets_Tracer_ActiveSpan()
         {
             var tracer = NoopTracerFactory.Create();
 
             var scope = tracer.BuildSpan("noop")
                 .StartActive(finishSpanOnDispose: false);
 
-            Assert.Null(tracer.ActiveSpan);
+            Assert.Same(NoopSpan.Instance, tracer.ActiveSpan);
         }
 
         [Fact]
-        public void StartActive_does_NOT_set_ScopeManager_Active()
+        public void StartActive_sets_ScopeManager_Active()
         {
             var tracer = NoopTracerFactory.Create();
 
             var scope = tracer.BuildSpan("noop")
                 .StartActive(finishSpanOnDispose: false);
 
-            Assert.Null(tracer.ScopeManager.Active);
+            Assert.Same(NoopScopeManager.NoopScope.Instance, tracer.ScopeManager.Active);
         }
 
         [Fact]
@@ -104,7 +105,7 @@ public void Start_returns_NoopSpan()
 
             var span = tracer.BuildSpan("noop").Start();
 
-            Assert.IsType<NoopSpan>(span);
+            Assert.Same(NoopSpan.Instance, span);
         }
 
         [Fact]
@@ -119,23 +120,23 @@ public void Start_always_returns_same_Span()
         }
 
         [Fact]
-        public void Start_does_NOT_set_Tracer_ActiveSpan()
+        public void Start_sets_Tracer_ActiveSpan()
         {
             var tracer = NoopTracerFactory.Create();
 
             var span = tracer.BuildSpan("noop").Start();
 
-            Assert.Null(tracer.ActiveSpan);
+            Assert.Same(NoopSpan.Instance, tracer.ActiveSpan);
         }
 
         [Fact]
-        public void Start_does_NOT_set_ScopeManager_Active()
+        public void Start_sets_ScopeManager_Active()
         {
             var tracer = NoopTracerFactory.Create();
 
             var span = tracer.BuildSpan("noop").Start();
 
-            Assert.Null(tracer.ScopeManager.Active);
+            Assert.Same(NoopScopeManager.NoopScope.Instance, tracer.ScopeManager.Active);
         }
 
         [Fact]
@@ -147,11 +148,11 @@ public void ScopeManager_returns_NoopScope_on_Activate()
 
             var scope = tracer.ScopeManager.Activate(span, finishSpanOnDispose: false);
 
-            Assert.IsType<NoopScopeManager.NoopScope>(scope);
+            Assert.Same(NoopScopeManager.NoopScope.Instance, scope);
         }
 
         [Fact]
-        public void ScopeManager_does_NOT_set_Active_on_Activate()
+        public void ScopeManager_sets_Active_on_Activate()
         {
             var tracer = NoopTracerFactory.Create();
 
@@ -159,8 +160,8 @@ public void ScopeManager_does_NOT_set_Active_on_Activate()
 
             tracer.ScopeManager.Activate(span, finishSpanOnDispose: false);
 
-            Assert.Null(tracer.ScopeManager.Active);
-            Assert.Null(tracer.ActiveSpan);
+            Assert.Same(NoopScopeManager.NoopScope.Instance, tracer.ScopeManager.Active);
+            Assert.Same(NoopSpan.Instance, tracer.ActiveSpan);
         }
 
         [Fact]
@@ -170,7 +171,7 @@ public void Span_has_NoopSpanContext()
 
             var span = tracer.BuildSpan("noop").Start();
 
-            Assert.IsType<NoopSpanContext>(span.Context);
+            Assert.Same(NoopSpanContext.Instance, span.Context);
         }
 
         [Fact]
@@ -182,7 +183,7 @@ public void Extract_returns_NoopSpanContext()
 
             var spanContext = tracer.Extract(BuiltinFormats.TextMap, new TextMapExtractAdapter(carrier));
 
-            Assert.IsType<NoopSpanContext>(spanContext);
+            Assert.Same(NoopSpanContext.Instance, spanContext);
         }
 
         [Fact]
diff --git a/test/OpenTracing.Tests/Noop/NoopTracerTests.cs b/test/OpenTracing.Tests/Noop/NoopTracerTests.cs
new file mode 100644
index 0000000..76fba1d
--- /dev/null
+++ b/test/OpenTracing.Tests/Noop/NoopTracerTests.cs
@@ -0,0 +1,18 @@
+using OpenTracing.Noop;
+using OpenTracing.Tag;
+using Xunit;
+
+namespace OpenTracing.Tests.Noop
+{
+    public class NoopTracerTest
+    {
+
+        [Fact]
+        public void ActiveSpanValueToleratesUse()
+        {
+            ISpan activeSpan = NoopTracer.Instance.ActiveSpan;
+            Assert.NotNull(activeSpan);
+            Tags.Error.Set(activeSpan, true);
+        }
+    }
+}