diff --git a/src/Markup/Perspex.Markup.Xaml/Context/PerspexNamespaceRegistry.cs b/src/Markup/Perspex.Markup.Xaml/Context/PerspexNamespaceRegistry.cs
index 4db1a89e7c..5efc4b2fa0 100644
--- a/src/Markup/Perspex.Markup.Xaml/Context/PerspexNamespaceRegistry.cs
+++ b/src/Markup/Perspex.Markup.Xaml/Context/PerspexNamespaceRegistry.cs
@@ -5,7 +5,6 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
-using Glass;
 using OmniXaml.Builder;
 using OmniXaml.Typing;
 using Perspex.Controls;
@@ -14,6 +13,7 @@ using Perspex.Media;
 using Perspex.Metadata;
 using Perspex.Platform;
 using Perspex.Styling;
+using Glass.Core;
 
 namespace Perspex.Markup.Xaml.Context
 {
diff --git a/src/Markup/Perspex.Markup.Xaml/Context/PerspexTypeRepository.cs b/src/Markup/Perspex.Markup.Xaml/Context/PerspexTypeRepository.cs
index 4fa8c4b281..4bcb7a20a6 100644
--- a/src/Markup/Perspex.Markup.Xaml/Context/PerspexTypeRepository.cs
+++ b/src/Markup/Perspex.Markup.Xaml/Context/PerspexTypeRepository.cs
@@ -2,10 +2,9 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System;
-using Glass;
 using OmniXaml;
 using OmniXaml.Typing;
-using Perspex.Markup.Xaml.Data;
+using Glass.Core;
 
 namespace Perspex.Markup.Xaml.Context
 {
diff --git a/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/StaticExtension.cs b/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/StaticExtension.cs
index ff01f8a461..7c89dd1e0d 100644
--- a/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/StaticExtension.cs
+++ b/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/StaticExtension.cs
@@ -4,8 +4,8 @@
 using System;
 using System.Linq;
 using System.Reflection;
-using Glass;
 using OmniXaml;
+using Glass.Core;
 
 namespace Perspex.Markup.Xaml.MarkupExtensions
 {
diff --git a/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/TypeExtension.cs b/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/TypeExtension.cs
index 65373e55cb..b82f8eb998 100644
--- a/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/TypeExtension.cs
+++ b/src/Markup/Perspex.Markup.Xaml/MarkupExtensions/TypeExtension.cs
@@ -2,10 +2,10 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System;
-using Glass;
 using OmniXaml;
 using OmniXaml.Attributes;
 using OmniXaml.Typing;
+using Glass.Core;
 
 namespace Perspex.Markup.Xaml.MarkupExtensions
 {