Although spermatorrhea as a disease entity and an episode in nineteenth-century medical history has received significant scholarly attention over the past decade, many aspects of its nature, origins, and consequences remain obscure. The aim of this article is to indicate its origins in and links with medical anxiety about masturbation and to discuss the therapies devised to treat the condition. Particular attention is given to the work of Claude-Francois Lallemand and his influence on English doctors, especially William Acton, and the implications of their identification of the foreskin as the major risk factor for childhood masturbation and later spermatorrhea. It is further argued that fear of spermatorrhea was an important factor in the acceptance of circumcision as a valid medical intervention in the late nineteenth century.