This book constitutes the thoroughly revised selected papers from the 17th International Symposium, FACS 2021, which was hel virtually in October 2021. The 7 full papers and 1 short contribution were carefully reviewed and selected from 16 submissions and are presented in the volume together with 1 invited paper. FACS 2021 is concerned with how formal methods can be applied to component-based software and system development. The book is subdivided into two blocks: Modelling & Composition and Verification. Chapter "A Linear Parallel Algorithm to Compute Bisimulation and Relational Coarsest Partitions" is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

This book constitutes the refereed proceedings of the 23rd International Symposium on Model Checking Software, SPIN 2016, held in Eindhoven, The Netherlands, in April 2016. The 16 papers presented, consisting of 11 regular papers, 1 idea paper, and 4 tool demonstrations, were carefully reviewed and selected from 27 submissions. Topics covered include model checking techniques, model checking tools, concurrent system semantics, equivalence checking, temporal logics, probabilistic systems, schedule and strategy synthesis using model checking, and verification case studies.