That would explain why the "CPU load increases linearly". If I understand the code properly each "+=" operation on the delegate adds another entry to the delegates list of functions to call. Looks like after running for a bit panel1_Paint is probably getting called god knows how many times (when once would suffice). Steve

I don't understand exactly what you're getting at - But based on my understanding (possibly flawed) here's what I'd do: class CMyClass { public:     CMyClass()     {         m_SomeVariable = 3; // Initialise member variable here.     }     void SomeFunction()     {         // Do something with "m_SomeVariable".     }     // .     // .     // Your stuff here.     // .     // . private:     int m_SomeVariable;         // The "m_" underscore is a common naming convention used for member variables. }