How did the complex concepts of psychoanalysis become popular in early twentieth-century Britain? This article examines the contribution of educator and psychoanalyst Susan Isaacs (1885–1948) to this process, as well as her role as a female expert in the intellectual and medical history of this period. Isaacs was one of the most influential British psychologists of the inter-war era, yet historical research on her work is still limited. The article focuses on her writing as ‘Ursula Wise’, answering the questions of parents and nursery nurses in the popular journal Nursery World, from 1929 to 1936. Researched in depth for the first time, Isaacs’ important magazine columns reveal that her writing was instrumental in disseminating the work of psychoanalyst Melanie Klein in Britain. Moreover, Isaacs’ powerful rebuttals to behaviourist, disciplinarian parenting methods helped shift the focus of caregivers to the child’s perspective, encouraging them to acknowledge children as independent subjects and future democratic citizens. Like other early psychoanalysts, Isaacs was not an elitist; she was in fact committed to disseminating her ideas as broadly as possible. Isaacs taught British parents and child caregivers to ‘speak Kleinian’, translating Klein’s intellectual ideas into ordinary language and thus enabling their swift integration into popular discourse.