We do hope that the present book will be useful for scholars who are interested in Don Pigozzi’s output, as well as in the areas, to the rise and development of which his work contributed, that is AAL, universal algebra and computer science. The published works contain new scientific results. Some of the papers also present chronologically ordered facts relating to the development of the disciplines, to the rise of which Don Pigozzi again contributed considerably, especially the abstract algebraic logic. The papers published in the volume will certainly offer valuable source material for historians of science, especially those who deal with the history of mathematics and logic.