Preface by Editor-in-Chief

The 9th Issue of LNCS Transactions on Petri Nets and Other Models of Concurrency (ToPNoC) contains revised and extended versions of a selection of the best papers from the workshops held at the 34th International Conference on Application and Theory of Petri Nets and Concurrency (Petri Nets 2013, Milan, Italy, during 24–28 June 2013), and 13th International Conference on Application of Concurrency to System Design (ACSD 2013, Barcelona, Spain, during 8–10 July 2013). It also contains one paper submitted directly to ToPNoC. I would like to thank the two guest editors of this special issue: Serge Haddad and Alex Yakovlev. Moreover, I would like to thank all authors, reviewers, and the organizers of the Petri Nets 2013 and ACSD 2013 conferences satellite workshops, without whom this issue of ToPNoC would not have been possible.