The work of psychiatrists affiliated with the Tavistock Clinic and Tavistock Institute has been credited with reshaping how workplaces were managed and with psychologising British society, providing British people with a new psychological language for thinking about problems. This thesis provides a history of the Second World War roots of this work. It examines two projects which emerged from a remarkable collaboration between the Tavistock group and the British Army: the War Office Selection Boards (WOSBs) and Civil Resettlement Units (CRUs). These projects, whose scale was vast and unprecedented in British human science, involved the creation and management of processes to choose leaders and to help communities disrupted by war to return ...