This book constitutes the refereed proceedings of the 4th International Symposium on Practical Aspects of Declarative Languages, PADL 2002, held in Portland, OR, USA in January 2002.The 18 revised full papers presented together with three invited contributions were carefully reviewed and selected from 37 submissions. Among the topics addressed are objects, ACL, higher order logic programming, compilers, embedded programs, types, XML parsing, texture generation, logic programming, generic programming, modeling languages, Prolog programming, garbage collection, etc.

This book constitutes the refereed proceedings of the 20th International Symposium on Model Checking Software, SPIN 2013, held in Stony Brook, NY, USA, in July 2013. The 18 regular papers, 2 tool demonstration papers, and 2 invited papers were carefully reviewed and selected from 40 submissions. The traditional focus of SPIN has been on explicit-state model checking techniques, as implemented in SPIN and other related tools. While such techniques are still of key interest to the workshop, its scope has broadened over recent years to include techniques for the verification and formal testing of software systems in general.

ETAPS2008wasthe11thinstanceoftheEuropeanJointConferencesonTheory and Practice of Software. ETAPS is an annual federated conference that was established in 1998 by combining a number of existing and new conferences. This yearit comprised?ve conferences (CC, ESOP,FASE, FOSSACS, TACAS), 22satelliteworkshops(ACCAT,AVIS,Bytecode,CMCS,COCV,DCC,FESCA, FIT, FORMED, GaLoP, GT-VMT, LDTA, MBT, MOMPES, PDMC, QAPL, RV,SafeCert,SC,SLA++P,WGT,andWRLA),ninetutorials,andseveninvited lectures (excluding those that were speci?c to the satellite events). The ?ve main conferences received 571 submissions, 147 of which were accepted, giving an overall acceptance rate of less than 26%, with each conference below 27%. Congratulationsthereforetoallthe authorswhomadeittothe ?nalprogramme! I hope that most of the other authors will still have found a way of participating in this exciting event, and that you will all continue submitting to ETAPS and contributing to make of it the best conference in the area. 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 the one hand and soundly based practice on the other. Many of the issues involved in software design apply to systems in general, including hardware s- tems, and the emphasis on software is not intended to be exclusive.