diff --git a/include/Nazara/Core/Signal.hpp b/include/Nazara/Core/Signal.hpp
index 69bf8fc28..2ff03b229 100644
--- a/include/Nazara/Core/Signal.hpp
+++ b/include/Nazara/Core/Signal.hpp
@@ -31,7 +31,7 @@ class NzSignal
 		template<typename O> Connection Connect(O& object, void (O::*method)(Args...));
 		template<typename O> Connection Connect(O* object, void (O::*method)(Args...));
 
-		void operator()(Args... args);
+		void operator()(Args... args) const;
 
 		NzSignal& operator=(const NzSignal&) = delete;
 		NzSignal& operator=(NzSignal&& signal);
diff --git a/include/Nazara/Core/Signal.inl b/include/Nazara/Core/Signal.inl
index c64ede1c8..6022329a7 100644
--- a/include/Nazara/Core/Signal.inl
+++ b/include/Nazara/Core/Signal.inl
@@ -59,7 +59,7 @@ typename NzSignal<Args...>::Connection NzSignal<Args...>::Connect(O* object, voi
 }
 
 template<typename... Args>
-void NzSignal<Args...>::operator()(Args... args)
+void NzSignal<Args...>::operator()(Args... args) const
 {
 	for (const SlotPtr& slot : m_slots)
 		slot->callback(args...);