This book constitutes the refereed proceedings of the 28th International Working Conference on Requirements Engineering: Foundation for Software Quality, REFSQ 2022, which was held in Aston, Birmingham, UK, during March 21-24, 2022. The 12 full and 7 short papers presented in this volume were carefully reviewed and selected from 45 submissions. They were organized in topical sections as follows: Artificial intelligence and explainability; machine learning; natural language processing; user stories; business, markets, and industrial practice; and cognition and expression. The special theme for REFSQ 2022 was "Explainability in Requirements Engineering".