Invited Papers -- Making Work Flow: On the Application of Petri Nets to Business Process Management -- Model Validation — A Theoretical Issue? -- The Real-Time Refinement Calculus: A Foundation for Machine-Independent Real-Time Programming -- The Challenge of Object Orientation for the Analysis of Concurrent Systems -- Abstract Cyclic Communicating Processes: A Logical View -- Is the Die Cast for the Token Game? -- Regular Papers -- Quasi-Static Scheduling of Independent Tasks for Reactive Systems -- Data Decision Diagrams for Petri Net Analysis -- Non-controllable Choice Robustness Expressing the Controllability of Workflow Processes -- Real-Time Synchronised Petri Nets -- Computing a Finite Prefix of a Time Petri Net -- Verification of a Revised WAP Wireless Transaction Protocol -- Characterizing Liveness of Petri Nets in Terms of Siphons -- Petri Nets, Situations, and Automata -- Reproducibility of the Empty Marking -- Modeling and Analysis of Multi-class Threshold-Based Queues with Hysteresis Using Stochastic Petri Nets -- Tackling the Infinite State Space of a Multimedia Control Protocol Service Specification -- Modelling of Features and Feature Interactions in Nokia Mobile Phones Using Coloured Petri Nets -- Analysing Infinite-State Systems by Combining Equivalence Reduction and the Sweep-Line Method -- Regular Event Structures and Finite Petri Nets: The Conflict-Free Case -- A Formal Service Specification for the Internet Open Trading Protocol -- Transition Refinement for Deriving a Distributed Minimum Weight Spanning Tree Algorithm -- Token-Controlled Place Refinement in Hierarchical Petri Nets with Application to Active Document Workflow -- Translating TPAL Specifications into Timed-Arc Petri Nets -- Tool Presentation -- Maria: Modular Reachability Analyser for Algebraic System Nets.