--- a/python/mozbuild/mozbuild/backend/visualstudio.py
+++ b/python/mozbuild/mozbuild/backend/visualstudio.py
@@ -35,22 +35,26 @@ from mozbuild.base import ExecutionSumma
 MSBUILD_NAMESPACE = 'http://schemas.microsoft.com/developer/msbuild/2003'
 
 def get_id(name):
     return str(uuid.uuid5(uuid.NAMESPACE_URL, name)).upper()
 
 def visual_studio_product_to_internal_version(version, solution=False):
     if version == '2013':
         return '12.00'
+    elif version == '2015':
+        return '14.00'
     else:
         raise Exception('Unknown version seen: %s' % version)
 
 def visual_studio_product_to_platform_toolset_version(version):
     if version == '2013':
         return 'v120'
+    elif version == '2015':
+        return 'v140'
     else:
         raise Exception('Unknown version seen: %s' % version)
 
 class VisualStudioBackend(CommonBackend):
     """Generate Visual Studio project files.
 
     This backend is used to produce Visual Studio projects and a solution
     to foster developing Firefox with Visual Studio.