diff --git a/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Components/BoundingBoxFollowerGraphicInspector.cs b/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Components/BoundingBoxFollowerGraphicInspector.cs
index a37a5e6a7..2c2585d8e 100644
--- a/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Components/BoundingBoxFollowerGraphicInspector.cs
+++ b/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Components/BoundingBoxFollowerGraphicInspector.cs
@@ -33,7 +33,7 @@
 
 using UnityEngine;
 using UnityEditor;
-using Boo.Lang;
+using System.Collections.Generic;
 
 namespace Spine.Unity.Editor {
 	using Event = UnityEngine.Event;