diff --git a/tasks/spec-task.coffee b/tasks/spec-task.coffee
index 4237bfd06..13ef31852 100644
--- a/tasks/spec-task.coffee
+++ b/tasks/spec-task.coffee
@@ -52,7 +52,9 @@ module.exports = (grunt) ->
       continue unless isAtomPackage(packagePath)
       packageSpecQueue.push(packagePath)
 
-    packageSpecQueue.concurrency = if process.platform is 'win32' then 2 else 1
+    # TODO: Restore concurrency on Windows
+    packageSpecQueue.concurrency = 1 unless process.platform is 'win32'
+
     packageSpecQueue.drain = -> callback(null, failedPackages)
 
   runCoreSpecs = (callback) ->
@@ -77,8 +79,10 @@ module.exports = (grunt) ->
       if process.platform is 'win32'
         process.stderr.write(fs.readFileSync('ci.log'))
         fs.unlinkSync('ci.log')
+      else
+        # TODO: Restore concurrency on Windows
+        packageSpecQueue.concurrency = 2
 
-      packageSpecQueue.concurrency = 2
       callback(null, error)
 
   grunt.registerTask 'run-specs', 'Run the specs', ->