Book excerpt: ​This book constitutes the proceedings of the 11th International Conference International Conference on Verification and Evaluation of Computer and Communication Systems ( VECoS 2017 ), held at Concordia University, Montreal, Canada, in August 2017. The 13 full papers, together with 3 abstracts in this volume were carefully reviewed and selected from 35 submissions. The aim of the VECoS conference is to bring together researchers and practitioners in the areas of verification, control, performance and dependability evalu-ation in order to discuss state-of-the-art and challenges in modern computer and communication systems in which functional and extra-functional properties are strongly interrelated. Thus, the main motivation for VECoS is to encourage the cross-fertilization between various formal verification and evaluation approaches, methods and techniques, and especially those developed for concurrent and dis-tributed hardware/software systems.