diff --git a/MCServer/Plugins/Debuggers/Debuggers.lua b/MCServer/Plugins/Debuggers/Debuggers.lua
index 484ea88b..f35e2d2d 100644
--- a/MCServer/Plugins/Debuggers/Debuggers.lua
+++ b/MCServer/Plugins/Debuggers/Debuggers.lua
@@ -588,9 +588,15 @@ function HandleTestWndCmd(a_Split, a_Player)
 		return (attempt <= 3);  -- refuse twice, then allow
 	end
 	
+	-- Log the slot changes
+	local OnSlotChanged = function(Window, SlotNum)
+		LOG("Window \"" .. Window:GetWindowTitle() .. "\" slot " .. SlotNum .. " changed.");
+	end
+	
 	local Window = cLuaWindow(WindowType, WindowSizeX, WindowSizeY, "TestWnd");
 	Window:SetSlot(a_Player, 0, cItem(E_ITEM_DIAMOND, 64));
 	Window:SetOnClosing(OnClosing);
+	Window:SetOnSlotChanged(OnSlotChanged);
 	
 	a_Player:OpenWindow(Window);
 	
diff --git a/source/LuaWindow.cpp b/source/LuaWindow.cpp
index 5ed52179..f6277250 100644
--- a/source/LuaWindow.cpp
+++ b/source/LuaWindow.cpp
@@ -25,6 +25,7 @@ cLuaWindow::cLuaWindow(cWindow::WindowType a_WindowType, int a_SlotsX, int a_Slo
 	m_OnClosingFnRef(LUA_REFNIL),
 	m_OnSlotChangedFnRef(LUA_REFNIL)
 {
+	m_Contents.AddListener(*this);
 	m_SlotAreas.push_back(new cSlotAreaItemGrid(m_Contents, *this));
 	
 	// If appropriate, add an Armor slot area:
@@ -96,6 +97,26 @@ void cLuaWindow::SetOnClosing(cPlugin_NewLua * a_Plugin, int a_FnRef)
 
 
 
+void cLuaWindow::SetOnSlotChanged(cPlugin_NewLua * a_Plugin, int a_FnRef)
+{
+	// Either m_Plugin is not set or equal to the passed plugin; only one plugin can use one cLuaWindow object
+	ASSERT((m_Plugin == NULL) || (m_Plugin == a_Plugin));
+	
+	// If there already was a function, unreference it first
+	if (m_OnSlotChangedFnRef != LUA_REFNIL)
+	{
+		m_Plugin->Unreference(m_OnSlotChangedFnRef);
+	}
+	
+	// Store the new reference
+	m_Plugin = a_Plugin;
+	m_OnSlotChangedFnRef = a_FnRef;
+}
+
+
+
+
+
 bool cLuaWindow::ClosedByPlayer(cPlayer & a_Player)
 {
 	// First notify the plugin through the registered callback:
@@ -133,3 +154,22 @@ void cLuaWindow::Destroy(void)
 
 
 
+
+void cLuaWindow::OnSlotChanged(cItemGrid * a_ItemGrid, int a_SlotNum)
+{
+	if (a_ItemGrid != &m_Contents)
+	{
+		ASSERT(!"Invalid ItemGrid in callback");
+		return;
+	}
+	
+	// If an OnSlotChanged callback has been registered, call it:
+	if (m_OnSlotChangedFnRef != LUA_REFNIL)
+	{
+		m_Plugin->CallbackWindowSlotChanged(m_OnSlotChangedFnRef, *this, a_SlotNum);
+	}
+}
+
+
+
+
diff --git a/source/LuaWindow.h b/source/LuaWindow.h
index 30c07bdb..dc4497df 100644
--- a/source/LuaWindow.h
+++ b/source/LuaWindow.h
@@ -10,6 +10,7 @@
 #pragma once
 
 #include "UI/Window.h"
+#include "ItemGrid.h"
 
 
 
@@ -35,7 +36,8 @@ cPlayer:OpenWindow check if the window is of this class, and if so, make a globa
 This reference needs to be unreferenced in the Destroy() function.
 */
 class cLuaWindow :
-	public cWindow
+	public cWindow,
+	public cItemGrid::cListener
 {
 	typedef cWindow super;
 	
@@ -83,6 +85,9 @@ protected:
 	// cWindow overrides:
 	virtual bool ClosedByPlayer(cPlayer & a_Player) override;
 	virtual void Destroy(void) override;
+	
+	// cItemGrid::cListener overrides:
+	virtual void OnSlotChanged(cItemGrid * a_ItemGrid, int a_SlotNum) override;
 } ;  // tolua_export
 
 
diff --git a/source/ManualBindings.cpp b/source/ManualBindings.cpp
index 96cd1437..0f8f1ad2 100644
--- a/source/ManualBindings.cpp
+++ b/source/ManualBindings.cpp
@@ -938,9 +938,13 @@ static int tolua_cPlayer_OpenWindow(lua_State * tolua_S)
 
 
 
-static int tolua_cLuaWindow_SetOnClosing(lua_State * tolua_S)
+template <
+	class OBJTYPE,
+	void (OBJTYPE::*SetCallback)(cPlugin_NewLua * a_Plugin, int a_FnRef)
+>
+static int tolua_SetObjectCallback(lua_State * tolua_S)
 {
-	// Function signature: cPlayer:SetOnClosing(CallbackFunction)
+	// Function signature: OBJTYPE:SetWhateverCallback(CallbackFunction)
 
 	// Retrieve the plugin instance from the Lua state
 	cPlugin_NewLua * Plugin = GetLuaPlugin(tolua_S);
@@ -950,14 +954,14 @@ static int tolua_cLuaWindow_SetOnClosing(lua_State * tolua_S)
 		return 0;
 	}
 
-	// Get the parameters:
-	cLuaWindow * self = (cLuaWindow *)tolua_tousertype(tolua_S, 1, NULL);
+	// Get the parameters - self and the function reference:
+	OBJTYPE * self = (OBJTYPE *)tolua_tousertype(tolua_S, 1, NULL);
 	if (self == NULL)
 	{
 		LOGWARNING("%s: invalid self (%p)", __FUNCTION__, self);
 		return 0;
 	}
-	int FnRef = luaL_ref(tolua_S, LUA_REGISTRYINDEX);  // Store function reference
+	int FnRef = luaL_ref(tolua_S, LUA_REGISTRYINDEX);  // Store function reference for later retrieval
 	if (FnRef == LUA_REFNIL)
 	{
 		LOGERROR("%s: Cannot create a function reference. Callback not set.", __FUNCTION__);
@@ -965,7 +969,7 @@ static int tolua_cLuaWindow_SetOnClosing(lua_State * tolua_S)
 	}
 	
 	// Set the callback
-	self->SetOnClosing(Plugin, FnRef);
+	(self->*SetCallback)(Plugin, FnRef);
 	return 0;
 }
 
@@ -1301,7 +1305,8 @@ void ManualBindings::Bind( lua_State* tolua_S )
 		tolua_endmodule(tolua_S);
 		
 		tolua_beginmodule(tolua_S, "cLuaWindow");
-			tolua_function(tolua_S, "SetOnClosing", tolua_cLuaWindow_SetOnClosing);
+			tolua_function(tolua_S, "SetOnClosing",     tolua_SetObjectCallback<cLuaWindow, &cLuaWindow::SetOnClosing>);
+			tolua_function(tolua_S, "SetOnSlotChanged", tolua_SetObjectCallback<cLuaWindow, &cLuaWindow::SetOnSlotChanged>);
 		tolua_endmodule(tolua_S);
 
 		tolua_beginmodule(tolua_S, "cPlugin_NewLua");
diff --git a/source/Plugin_NewLua.cpp b/source/Plugin_NewLua.cpp
index dd3db7d6..a76b5180 100644
--- a/source/Plugin_NewLua.cpp
+++ b/source/Plugin_NewLua.cpp
@@ -1667,6 +1667,8 @@ void cPlugin_NewLua::Unreference(int a_LuaRef)
 
 bool cPlugin_NewLua::CallbackWindowClosing(int a_FnRef, cWindow & a_Window, cPlayer & a_Player)
 {
+	ASSERT(a_FnRef != LUA_REFNIL);
+	
 	cCSLock Lock(m_CriticalSection);
 	lua_rawgeti(m_LuaState, LUA_REGISTRYINDEX, a_FnRef);  // Push the function to be called
 	tolua_pushusertype(m_LuaState, &a_Window, "cWindow");
@@ -1689,6 +1691,27 @@ bool cPlugin_NewLua::CallbackWindowClosing(int a_FnRef, cWindow & a_Window, cPla
 
 
 
+void cPlugin_NewLua::CallbackWindowSlotChanged(int a_FnRef, cWindow & a_Window, int a_SlotNum)
+{
+	ASSERT(a_FnRef != LUA_REFNIL);
+	
+	cCSLock Lock(m_CriticalSection);
+	lua_rawgeti(m_LuaState, LUA_REGISTRYINDEX, a_FnRef);  // Push the function to be called
+	tolua_pushusertype(m_LuaState, &a_Window, "cWindow");
+	tolua_pushnumber  (m_LuaState, a_SlotNum);
+
+	// Call function:
+	int s = lua_pcall(m_LuaState, 2, 0, 0);
+	if (report_errors(m_LuaState, s))
+	{
+		LOGERROR("LUA error in %s. Stack size: %i", __FUNCTION__, lua_gettop(m_LuaState));
+	}
+}
+
+
+
+
+
 // Helper functions
 bool cPlugin_NewLua::PushFunction(const char * a_FunctionName, bool a_bLogError /* = true */)
 {
diff --git a/source/Plugin_NewLua.h b/source/Plugin_NewLua.h
index fc3565bb..34ab85ca 100644
--- a/source/Plugin_NewLua.h
+++ b/source/Plugin_NewLua.h
@@ -108,6 +108,9 @@ public:
 	/// Calls the plugin-specified "cLuaWindow closing" callback. Returns true only if the callback returned true
 	bool CallbackWindowClosing(int a_FnRef, cWindow & a_Window, cPlayer & a_Player);
 	
+	/// Calls the plugin-specified "cLuaWindow slot changed" callback.
+	void CallbackWindowSlotChanged(int a_FnRef, cWindow & a_Window, int a_SlotNum);
+	
 protected:
 	cCriticalSection m_CriticalSection;
 	lua_State * m_LuaState;