Klaus Holzkamp (1927–1995) was a professor at Free University Berlin and the founder of German Critical Psychology, which worked towards a renewal of academic psychology. His ideas inspired and mobilized generations of young researchers and practitioners who were discontented with the socio-political function of psychology and the human sciences. Although his approach has been discussed internationally, much of his work is not available in English. With this book we offer a selection of his writings in order to introduce the reader to the central ideas of Holzkamp's psychology from the standpoint of the subject.