The business of birth control is the first book-length study to examine contraceptives as commodities in Britain before the advent of the Pill in the 1960s. Drawing on new archives and neglected promotional and commercial materials, the book demonstrates how hundreds of companies transformed condoms, douches and pessaries into consumer goods. These products became widely available via discreet mail-order catalogues, newspapers, birth control clinics, chemists’ shops and vending machines. With its focus on the interwar period, the book demonstrates how contraceptive commodification shaped sexual and birth control knowledge and practice at a time when older, more restrictive moral values surrounding sexuality uncomfortably co-existed with a vision of the future promised by science, medicine and technology. The commodification of birth control came into conflict with medicalisation efforts by the state, the medical profession and the birth control movement, as well as attempts at censorship by social purity groups that sought to maintain sexual ignorance among much of the population. Drawing on approaches from the history of medicine, material and print culture studies and social and cultural history, the book serves as an important reminder that businesses were integral to shaping medical, economic, social and cultural attitudes towards sex and birth control. Additionally, it sheds new light on the ambiguities and tensions of interwar Britain more broadly and demonstrates how the contraceptive Pill emerged from these interwar struggles.