ETAPS 2002 is the ?fth instance of the European Joint Conferences on Theory and Practice of Software. ETAPS is an annual federated conference that was established in 1998by combining a number of existing and new conferences. This year it comprises ?ve conferences (FOSSACS, FASE, ESOP, CC, TACAS), thirteen satellite workshops (ACL2, AGT, CMCS, COCV, DCC, INT, LDTA, SC, SFEDL, SLAP, SPIN, TPTS and VISS), eight invited lectures (not including those that are speci?c to the satellite events), and several tutorials. The events that comprise ETAPS address various aspects of the system - velopment process, including speci?cation, design, implementation, analysis and improvement. The languages, methodologies and tools which support these - tivities are all well within its scope. Di?erent blends of theory and practice are represented, with an inclination towards theory with a practical motivation on one hand and soundly-based practice on the other. Many of the issues involved in software design apply to systems in general, including hardware systems, and the emphasis on software is not intended to be exclusive.

Invited Paper.- Semantical Evaluations as Monadic Second-Order Compatible Structure Transformations.- Contributed Papers.- Verification for Java's Reentrant Multithreading Concept.- On the Integration of Observability and Reachability Concepts.- Proving Correctness of Timed Concurrent Constraint Programs.- Generalised Regular MSC Languages.- On Compositional Reasoning in the Spi-calculus.- On Specification Logics for Algebra-Coalgebra Structures: Reconciling Reachability and Observability.- A First-Order One-Pass CPS Transformation.- The Demonic Product of Probabilistic Relations.- Minimizing Transition Systems for Name Passing Calculi: A Co-algebraic Formulation.- Varieties of Effects.- A Characterization of Families of Graphs in Which Election Is Possible.- Equivalence-Checking with One-Counter Automata: A Generic Method for Proving Lower Bounds*.- Efficient Type Matching.- Higher-Order Pushdown Trees Are Easy.- Conflict Detection and Resolution in Access Control Policy Specifications.- Logics Admitting Final Semantics.- Model Checking Fixed Point Logic with Chop.- On Model Checking Durational Kripke Structures.- Model-Checking Infinite Systems Generated by Ground Tree Rewriting.- Bounded MSC Communication.- The Informatic Derivative at a Compact Element.- Heterogeneous Development Graphs and Heterogeneous Borrowing.- Notions of Computation Determine Monads.- A Calculus of Circular Proofs and Its Categorical Semantics.- Verifying Temporal Properties Using Explicit Approximants: Completeness for Context-free Processes.- Note on the Tableau Technique for Commutative Transition Systems.- A Semantic Basis for Local Reasoning.- Linearity and Bisimulation.