This book constitutes the refereed proceedings of the 25th International Conference on Applications and Theory of Petri Nets, ICATPN 2004, held in Bologna, Italy in June 2004.

The 19 revised full regular papers and 5 revised tool presentation papers presented together with 6 invited papers were carefully reviewed and selected from 62 submissions. All current issues on research and development in the area of Petri nets are addressed, in particular concurrent systems design and analysis, modular systems development, formal specification, model validation, model checking, workflow management, flow charts, networking, formal methods in software engineering, etc.