diff --git a/src/EditorFeatures/Test2/Diagnostics/DiagnosticServiceTests.vb b/src/EditorFeatures/Test2/Diagnostics/DiagnosticServiceTests.vb
index 55f3a531d47801715f6a4378cc7ec94e7e5ea06c..52b94238e9db1f8aea397be28a813c9ffd6f1c29 100644
--- a/src/EditorFeatures/Test2/Diagnostics/DiagnosticServiceTests.vb
+++ b/src/EditorFeatures/Test2/Diagnostics/DiagnosticServiceTests.vb
@@ -10,6 +10,7 @@ Imports Microsoft.CodeAnalysis.Diagnostics
 Imports Microsoft.CodeAnalysis.Editor.UnitTests.Diagnostics
 Imports Microsoft.CodeAnalysis.Editor.UnitTests.Workspaces
 Imports Microsoft.CodeAnalysis.Options
+Imports Microsoft.CodeAnalysis.Shared.Options
 Imports Microsoft.CodeAnalysis.Test.Utilities
 Imports Microsoft.CodeAnalysis.Text
 Imports Microsoft.CodeAnalysis.UnitTests.Diagnostics
@@ -1915,6 +1916,9 @@ class MyClass
                        </Workspace>
 
             Using workspace = TestWorkspace.CreateWorkspace(test)
+                ' set csharp closed diagnostic option on
+                workspace.Options = workspace.Options.WithChangedOption(ServiceFeatureOnOffOptions.ClosedFileDiagnostic, LanguageNames.CSharp, True)
+
                 Dim project = workspace.CurrentSolution.Projects.Single()
 
                 ' Add analyzer
diff --git a/src/Features/Core/Portable/Shared/Options/ServiceFeatureOnOffOptions.cs b/src/Features/Core/Portable/Shared/Options/ServiceFeatureOnOffOptions.cs
index 4d747c45e9928dbdda35e12187c238756a81827e..2611ec985411679274fc969cbe59c63d178f0054 100644
--- a/src/Features/Core/Portable/Shared/Options/ServiceFeatureOnOffOptions.cs
+++ b/src/Features/Core/Portable/Shared/Options/ServiceFeatureOnOffOptions.cs
@@ -1,5 +1,6 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections.Immutable;
 using Microsoft.CodeAnalysis.Options;
 
 namespace Microsoft.CodeAnalysis.Shared.Options
@@ -13,6 +14,7 @@ internal static class ServiceFeatureOnOffOptions
         /// this option doesn't mean we will show all diagnostics that belong to opened files when turned off,
         /// rather it means we will only show diagnostics that are cheap to calculate for small scope such as opened files.
         /// </summary>
-        public static readonly PerLanguageOption<bool> ClosedFileDiagnostic = new PerLanguageOption<bool>(OptionName, "Closed File Diagnostic", defaultValue: true);
+        public static readonly PerLanguageOption<bool> ClosedFileDiagnostic = new PerLanguageOption<bool>(
+            OptionName, "Closed File Diagnostic", defaultValue: true, perLanguageDefaults: ImmutableDictionary<string, bool>.Empty.Add(LanguageNames.CSharp, false));
     }
 }
diff --git a/src/VisualStudio/Core/Impl/Options/AbstractSettingStoreOptionSerializer.cs b/src/VisualStudio/Core/Impl/Options/AbstractSettingStoreOptionSerializer.cs
index bcd282f6fe838993a08b3db1b944d224c0ad6b44..dc87ba018ab1cb08fb284f5674a6c54e28176a09 100644
--- a/src/VisualStudio/Core/Impl/Options/AbstractSettingStoreOptionSerializer.cs
+++ b/src/VisualStudio/Core/Impl/Options/AbstractSettingStoreOptionSerializer.cs
@@ -34,7 +34,7 @@ public virtual bool TryPersist(OptionKey optionKey, object value)
             return TryPersist(optionKey, value, (r, k, o, v) => r.SetValue(k, (bool)v ? 1 : 0, RegistryValueKind.DWord));
         }
 
-        protected bool TryFetch(OptionKey optionKey, Func<RegistryKey, string, IOption, object> valueGetter, out object value)
+        protected bool TryFetch(OptionKey optionKey, Func<RegistryKey, string, OptionKey, object> valueGetter, out object value)
         {
             if (this.RegistryKey == null)
             {
@@ -58,7 +58,7 @@ protected bool TryFetch(OptionKey optionKey, Func<RegistryKey, string, IOption,
                         return false;
                     }
 
-                    value = valueGetter(subKey, collectionPathAndPropertyName.Item2, optionKey.Option);
+                    value = valueGetter(subKey, collectionPathAndPropertyName.Item2, optionKey);
                     return true;
                 }
             }
diff --git a/src/VisualStudio/Core/Impl/Options/AbstractSettingsManagerOptionSerializer.cs b/src/VisualStudio/Core/Impl/Options/AbstractSettingsManagerOptionSerializer.cs
index 39678aa3aff238e213998070344b9ee7245de843..3b3f20a7652b5c50b542c583a72358cf45f5a9f5 100644
--- a/src/VisualStudio/Core/Impl/Options/AbstractSettingsManagerOptionSerializer.cs
+++ b/src/VisualStudio/Core/Impl/Options/AbstractSettingsManagerOptionSerializer.cs
@@ -146,7 +146,7 @@ public virtual bool TryFetch(OptionKey optionKey, out object value)
             }
 
             var storageKey = GetStorageKeyForOption(optionKey.Option);
-            value = this.Manager.GetValueOrDefault(storageKey, optionKey.Option.DefaultValue);
+            value = this.Manager.GetValueOrDefault(storageKey, optionKey.DefaultValue);
 
             return true;
         }
diff --git a/src/Workspaces/Core/Portable/Options/IOption2.cs b/src/Workspaces/Core/Portable/Options/IOption2.cs
new file mode 100644
index 0000000000000000000000000000000000000000..857604f38d947640f5e59feccf0fe3b663427b35
--- /dev/null
+++ b/src/Workspaces/Core/Portable/Options/IOption2.cs
@@ -0,0 +1,9 @@
+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+namespace Microsoft.CodeAnalysis.Options
+{
+    internal interface IOption2 : IOption
+    {
+        object GetDefaultValue(string language);
+    }
+}
diff --git a/src/Workspaces/Core/Portable/Options/OptionKey.cs b/src/Workspaces/Core/Portable/Options/OptionKey.cs
index f4956d401678a46cb31935d1e92d07fda4aa359a..8300af2f144d147d09b91103c8d1bd27454742e7 100644
--- a/src/Workspaces/Core/Portable/Options/OptionKey.cs
+++ b/src/Workspaces/Core/Portable/Options/OptionKey.cs
@@ -10,6 +10,8 @@ public struct OptionKey : IEquatable<OptionKey>
         public IOption Option { get; }
         public string Language { get; }
 
+        internal object DefaultValue => ((IOption2)Option).GetDefaultValue(Language);
+
         public OptionKey(IOption option, string language = null)
         {
             if (option == null)
diff --git a/src/Workspaces/Core/Portable/Options/OptionService.cs b/src/Workspaces/Core/Portable/Options/OptionService.cs
index de73f3c956e4eb536fea71fa10a7f035017e27b6..c6a30107eff9d131de505d2a36d9fb2ca0d8817e 100644
--- a/src/Workspaces/Core/Portable/Options/OptionService.cs
+++ b/src/Workspaces/Core/Portable/Options/OptionService.cs
@@ -81,7 +81,7 @@ private object LoadOptionFromSerializerOrGetDefault(OptionKey optionKey)
 
                 // Just use the default. We will still cache this so we aren't trying to deserialize
                 // over and over.
-                return optionKey.Option.DefaultValue;
+                return optionKey.DefaultValue;
             }
         }
 
diff --git a/src/Workspaces/Core/Portable/Options/OptionSet.cs b/src/Workspaces/Core/Portable/Options/OptionSet.cs
index eac193bb2ec29be8dcef1b7dc6fe855628b5c90f..2c9acd7f0f939061ccef1cb6a7fca9c5d1e5d279 100644
--- a/src/Workspaces/Core/Portable/Options/OptionSet.cs
+++ b/src/Workspaces/Core/Portable/Options/OptionSet.cs
@@ -51,7 +51,7 @@ public object GetOption(OptionKey optionKey)
 
                 if (!_values.TryGetValue(optionKey, out value))
                 {
-                    value = _service != null ? _service.GetOption(optionKey) : optionKey.Option.DefaultValue;
+                    value = _service != null ? _service.GetOption(optionKey) : optionKey.DefaultValue;
                     _values = _values.Add(optionKey, value);
                 }
 
diff --git a/src/Workspaces/Core/Portable/Options/Option`1.cs b/src/Workspaces/Core/Portable/Options/Option`1.cs
index 5c8bea66b814e9cd5c1ff65170cc6dc3f96e2e6f..521c7414f3fa01ad702a85d5e2f4979f89390295 100644
--- a/src/Workspaces/Core/Portable/Options/Option`1.cs
+++ b/src/Workspaces/Core/Portable/Options/Option`1.cs
@@ -7,7 +7,7 @@ namespace Microsoft.CodeAnalysis.Options
     /// <summary>
     /// An global option. An instance of this class can be used to access an option value from an OptionSet.
     /// </summary>
-    public class Option<T> : IOption
+    public class Option<T> : IOption2, IOption
     {
         /// <summary>
         /// Feature this option is associated with.
@@ -22,10 +22,7 @@ public class Option<T> : IOption
         /// <summary>
         /// The type of the option value.
         /// </summary>
-        public Type Type
-        {
-            get { return typeof(T); }
-        }
+        public Type Type => typeof(T);
 
         /// <summary>
         /// The default value of the option.
@@ -49,19 +46,13 @@ public Option(string feature, string name, T defaultValue = default(T))
             this.DefaultValue = defaultValue;
         }
 
-        Type IOption.Type
-        {
-            get { return typeof(T); }
-        }
-
-        object IOption.DefaultValue
-        {
-            get { return this.DefaultValue; }
-        }
+        Type IOption.Type => typeof(T);
+        object IOption.DefaultValue => this.DefaultValue;
+        bool IOption.IsPerLanguage => false;
 
-        bool IOption.IsPerLanguage
+        object IOption2.GetDefaultValue(string language)
         {
-            get { return false; }
+            return this.DefaultValue;
         }
 
         public override string ToString()
diff --git a/src/Workspaces/Core/Portable/Options/PerLanguageOption.cs b/src/Workspaces/Core/Portable/Options/PerLanguageOption.cs
index 23398e14ad9820611e827aab1571fd9e26d1e0e9..ae04592fb490fe3b2c18eb0ab82955f426a83f5a 100644
--- a/src/Workspaces/Core/Portable/Options/PerLanguageOption.cs
+++ b/src/Workspaces/Core/Portable/Options/PerLanguageOption.cs
@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
 
 namespace Microsoft.CodeAnalysis.Options
 {
@@ -8,8 +10,13 @@ namespace Microsoft.CodeAnalysis.Options
     /// An option that can be specified once per language.
     /// </summary>
     /// <typeparam name="T"></typeparam>
-    public class PerLanguageOption<T> : IOption
+    public class PerLanguageOption<T> : IOption2, IOption
     {
+        /// <summary>
+        /// Save per language defaults
+        /// </summary>
+        private readonly IImmutableDictionary<string, T> _perLanguageDefaults;
+
         /// <summary>
         /// Feature this option is associated with.
         /// </summary>
@@ -33,7 +40,32 @@ public Type Type
         /// </summary>
         public T DefaultValue { get; }
 
-        public PerLanguageOption(string feature, string name, T defaultValue)
+        /// <summary>
+        /// The default option value of specific language
+        /// </summary>
+        internal T GetDefaultValue(string language)
+        {
+            if (_perLanguageDefaults.Count == 0)
+            {
+                return DefaultValue;
+            }
+
+            T languageSpecificDefault;
+            if (!_perLanguageDefaults.TryGetValue(language, out languageSpecificDefault))
+            {
+                return DefaultValue;
+            }
+
+            return languageSpecificDefault;
+        }
+
+        public PerLanguageOption(string feature, string name, T defaultValue) :
+            this(feature, name, defaultValue, ImmutableDictionary<string, T>.Empty)
+        {
+        }
+
+        internal PerLanguageOption(
+            string feature, string name, T defaultValue, IDictionary<string, T> perLanguageDefaults)
         {
             if (string.IsNullOrWhiteSpace(feature))
             {
@@ -45,9 +77,18 @@ public PerLanguageOption(string feature, string name, T defaultValue)
                 throw new ArgumentException(nameof(name));
             }
 
+            if (perLanguageDefaults == null)
+            {
+                throw new ArgumentNullException(nameof(perLanguageDefaults));
+            }
+
             this.Feature = feature;
             this.Name = name;
             this.DefaultValue = defaultValue;
+
+            this._perLanguageDefaults =
+                (perLanguageDefaults as IImmutableDictionary<string, T>) ??
+                        ImmutableDictionary.CreateRange<string, T>(perLanguageDefaults);
         }
 
         Type IOption.Type
@@ -65,6 +106,11 @@ bool IOption.IsPerLanguage
             get { return true; }
         }
 
+        object IOption2.GetDefaultValue(string language)
+        {
+            return this.GetDefaultValue(language);
+        }
+
         public override string ToString()
         {
             return string.Format("{0} - {1}", this.Feature, this.Name);
diff --git a/src/Workspaces/Core/Portable/Workspaces.csproj b/src/Workspaces/Core/Portable/Workspaces.csproj
index 6e59591f1bb84d705cde514902e23ab1518abe14..2dcb9fbdcee9244d5754050217d0a2fe3d2e45c7 100644
--- a/src/Workspaces/Core/Portable/Workspaces.csproj
+++ b/src/Workspaces/Core/Portable/Workspaces.csproj
@@ -387,6 +387,7 @@
     <Compile Include="FindSymbols\DeclaredSymbolInfo.cs" />
     <Compile Include="FindSymbols\FindReferences\Finders\ILanguageServiceReferenceFinder.cs" />
     <Compile Include="LinkedFileDiffMerging\LinkedFileDiffMergingLogger.cs" />
+    <Compile Include="Options\IOption2.cs" />
     <Compile Include="Packaging\IPackageInstallerService.cs" />
     <Compile Include="Packaging\IPackageSearchService.cs" />
     <Compile Include="FindSymbols\SymbolTree\ISymbolTreeInfoCacheService.cs" />