This book constitutes the proceedings of the 17th International Conference on Theoretical Aspects of Software Engineering, TASE 2023, held in Bristol, UK, July 4–6, 2023.The 19 full papers and 2 short papers included in this book were carefully reviewed and selected from 49 submissions. They were organized in topical sections as follows: systems with runtime assurance architectures; asynchronous test equivalence over timed processes; and stepwise development of paraconsistent processes. weiterlesen