This book constitutes the refereed proceedings of the 10th International Workshop on Abstract State Machines, ASM 2003, held in Taormina, Italy in March 2003.

The 16 revised full papers presented together with 8 invited papers and 12 abstracts were carefully reviewed and selected for inclusion in the book. The papers reflect the state of the art of the abstract state machine method for the design and analysis of complex software/hardware systems. Besides theoretical results and methodological progress, application in various fields are studied as well.

This volume contains the proceedings of TAP 2010, the 4th International C- ference on Tests and Proofs held during July 1 2 in M alaga, Spain as part of TOOLS Federated Conferences. TAP 2010wasthe fourth event of an ongoingseriesof conferencesdevoted to the convergence of proofs and tests. In the past, proving and testing were seen as very di?erent and even competing techniques. Proving people would say: If correctness is proved, what do we need tests for? Testers, on the other hand, would claim that proving is too limited in applicability and testing is the only truepathtocorrectness....