diff --git a/Implab/JSON/JSONWriter.cs b/Implab/JSON/JSONWriter.cs
--- a/Implab/JSON/JSONWriter.cs
+++ b/Implab/JSON/JSONWriter.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Globalization;
 
 namespace Implab.JSON {
     public class JSONWriter {
@@ -35,7 +36,6 @@ namespace Implab.JSON {
 
         public JSONWriter(TextWriter writer) {
             Safe.ArgumentNotNull(writer, "writer");
-
             m_writer = writer;
         }
 
@@ -262,7 +262,14 @@ namespace Implab.JSON {
         }
 
         void Write(double value) {
-            m_writer.Write(value);
+            if (double.IsNaN(value))
+                Write("NaN");
+            else if (double.IsNegativeInfinity(value))
+                Write("-Infinity");
+            else if (double.IsPositiveInfinity(value))
+                Write("Infinity");
+            else
+                m_writer.Write(value.ToString(CultureInfo.InvariantCulture));
         }
 
         void OperationNotApplicable(string opName) {