This book constitutes the refereed proceedings of the 11th International Conference on Rigorous State-Based Methods, ABZ 2025, held in Düsseldorf, Germany, during June 10–13, 2025.The 10 full papers, 4 short papers, 2 PhD Symposium papers and 5 case study papers presented in this book were carefully reviewed and selected from 33 submissions. The proceedings also contain one invited talk in full paper length. The ABZ conference series is dedicated to the cross-fertilization of state-based and machine-based formal methods. Abstract State Machines (ASM), Alloy, B, TLA, VDM, and Z are examples of these methods. They share a common conceptual foundation and are widely used in both academia and industry for the rigorous design and analysis of hardware and software systems. The ABZ conferences aim to be a forum for the vital exchange of knowledge and experience among the research communities around different formal methods.
