Dr John Black, military historian and former pay sergeant, delves into the often-neglected history of the British Army Pay Services during the First World War. Drawing on his own service in the RAMC and RAPC, Black explores the work of the Pay Department, Pay Corps and the clerical staff—both military and civilian—who ensured that the army’s financial machinery ran smoothly amidst the chaos of war. His research reveals a critical yet underappreciated aspect of the wartime effort.