diff --git a/Eluant/LuaClrObjectValue.cs b/Eluant/LuaClrObjectValue.cs
index 1498468..be45862 100644
--- a/Eluant/LuaClrObjectValue.cs
+++ b/Eluant/LuaClrObjectValue.cs
@@ -58,7 +58,7 @@ public override string ToString()
 
         internal abstract object BackingCustomObject { get; }
 
-        internal abstract MetamethodAttribute[] BackingCustomObjectMetamethods { get; }
+        internal abstract MetamethodAttribute[] BackingCustomObjectMetamethods(LuaRuntime runtime);
 
         static internal MetamethodAttribute[] Metamethods(Type backingCustomObjectType)
         {
diff --git a/Eluant/LuaCustomClrObject.cs b/Eluant/LuaCustomClrObject.cs
index 18dda5b..946cffc 100644
--- a/Eluant/LuaCustomClrObject.cs
+++ b/Eluant/LuaCustomClrObject.cs
@@ -57,9 +57,9 @@ internal override object BackingCustomObject
 
         private MetamethodAttribute[] metamethods;
 
-        internal override MetamethodAttribute[] BackingCustomObjectMetamethods
+        internal override MetamethodAttribute[] BackingCustomObjectMetamethods(LuaRuntime runtime)
         {
-            get { return metamethods ?? (metamethods = Metamethods(BackingCustomObject.GetType())); }
+            return metamethods ?? (metamethods = runtime.CachedMetamethods(BackingCustomObject.GetType()));
         }
     }
 }
diff --git a/Eluant/LuaOpaqueClrObject.cs b/Eluant/LuaOpaqueClrObject.cs
index 1531f16..b6ebd45 100644
--- a/Eluant/LuaOpaqueClrObject.cs
+++ b/Eluant/LuaOpaqueClrObject.cs
@@ -55,9 +55,9 @@ internal override object BackingCustomObject
             get { return null; }
         }
 
-        internal override MetamethodAttribute[] BackingCustomObjectMetamethods
+        internal override MetamethodAttribute[] BackingCustomObjectMetamethods(LuaRuntime runtime)
         {
-            get { return null; }
+            return null;
         }
     }
 }
diff --git a/Eluant/LuaRuntime.cs b/Eluant/LuaRuntime.cs
index adeda17..e885e7d 100644
--- a/Eluant/LuaRuntime.cs
+++ b/Eluant/LuaRuntime.cs
@@ -78,6 +78,7 @@ protected GCHandle SelfHandle
         private const string OPAQUECLROBJECT_METATABLE = "eluant_opaqueclrobject";
 
         private Dictionary<string, LuaFunction> metamethodCallbacks = new Dictionary<string, LuaFunction>();
+        private Dictionary<Type, MetamethodAttribute[]> metamethodAttributes = new Dictionary<Type, MetamethodAttribute[]>();
 
         private LuaFunction createManagedCallWrapper;
 
@@ -778,7 +779,7 @@ internal void PushCustomClrObject(LuaClrObjectValue obj)
                 LuaApi.lua_settable(LuaState, -3);
 
                 // For all others, we use MetamethodAttribute on the interface to make this code less repetitive.
-                foreach (var metamethod in obj.BackingCustomObjectMetamethods) {
+                foreach (var metamethod in obj.BackingCustomObjectMetamethods(this)) {
                     LuaApi.lua_pushstring(LuaState, metamethod.MethodName);
                     Push(metamethodCallbacks[metamethod.MethodName]);
                     LuaApi.lua_settable(LuaState, -3);
@@ -791,6 +792,19 @@ internal void PushCustomClrObject(LuaClrObjectValue obj)
             }
         }
 
+        internal MetamethodAttribute[] CachedMetamethods(Type backingCustomObjectType)
+        {
+            MetamethodAttribute[] metamethods;
+            if (metamethodAttributes.TryGetValue(backingCustomObjectType, out metamethods)) {
+                return metamethods;
+            }
+
+            metamethods = LuaClrObjectValue.Metamethods(backingCustomObjectType);
+            metamethodAttributes.Add(backingCustomObjectType, metamethods);
+
+            return metamethods;
+        }
+
         private int NewindexCallback(IntPtr state)
         {
             return LuaToClrBoundary(state, toDispose => {
diff --git a/Eluant/LuaTransparentClrObject.cs b/Eluant/LuaTransparentClrObject.cs
index 42b6daa..936136e 100644
--- a/Eluant/LuaTransparentClrObject.cs
+++ b/Eluant/LuaTransparentClrObject.cs
@@ -73,9 +73,9 @@ internal override object BackingCustomObject
             get { return proxy; }
         }
 
-        internal override MetamethodAttribute[] BackingCustomObjectMetamethods
+        internal override MetamethodAttribute[] BackingCustomObjectMetamethods(LuaRuntime runtime)
         {
-            get { return TransparentClrObjectProxy.Metamethods; }
+            return TransparentClrObjectProxy.Metamethods;
         }
 
         private class TransparentClrObjectProxy : ILuaTableBinding, ILuaEqualityBinding