The aim of this book is to present the heritage of the Lvov-Warsaw School from both the historical and the philosophical perspective. The historical view is focused on the beginnings and the dramatic end of the School brought about by the outbreak of World War II. The philosophical view, on the other hand, encompasses a broad spectrum of issues, including logical, epistemological, axiological, and psychological problems. It should be emphasised that the philosophical perspective reveals the interdisciplinary nature of studies carried out by Kazimierz Twardowski and his students. The School’s achievements range across philosophy, ethics, psychology, logic, and mathematics. This volume, entitled ‘Interdisciplinary Investigations into the Lvov-Warsaw School,’ consists of three parts: (1) History, Culture, and Axiology; (2) Psychology; (3) Logic and Methodology.