Welcome to the proceedings of the 19th International Workshop on Power and TimingModeling, OptimizationandSimulation, PATMOS2009.Overtheyears, PATMOShasevolvedintoanimportantEuropeanevent, whereresearchersfrom both industry and academia discuss and investigate the emerging challenges in future and contemporary applications, design methodologies, and tools required for the development of the upcoming generations of integrated circuits and s- tems...