This book constitutes the proceedings of the 43rd International Conference on Application and Theory of Petri Nets and Concurrency, PETRI NETS 2022, which was held virtually in June 2021. The 19 full papers presented in this volume were carefully reviewed and selected from 35 submissions. The papers are categorized into the following topical sub-headings: application of concurrency to system design; timed models; tools; applications; synthesis; petri nets architecture; and process mining.