This work deals with the groundbreaking development theory and sociology of Richard F. Behrendt, which has largely been forgotten since his death in 1972. Behrendt addresses issues of social change in his entire body of work and offers a comprehensive concept of sustainable and inclusive development strategies. The author analyzes Behrendt's theory of socio-economic development, his conception of development sociology, and its social scientific and epistemological foundations, taking into account Behrendt's life, which corresponds in a special way to his overall work. Based on Behrendt's complete works, the author outlines the principles and measures that can ensure the effectiveness and sustainability of development promotion. The book also includes a systematic and complete bibliography of Richard F. Behrendt.