Clinical research, especially in psychiatry, takes place in a field of tensions: between economic, scientific, ethical, and therapeutic interests; between the individual and society; between law, guidelines, and the need for safety, as well as the awareness that clinical studies always involve residual risk. After the Second World War, large numbers of psychotropic drugs were tested for decades in the Münsterlingen Psychiatric Clinic, a state-run hospital in eastern Switzerland. The driving force behind these trials was Roland Kuhn, an internationally renowned psychiatrist hailed by many as the ‘discoverer’ of the first antidepressant, Tofranil. Based on Kuhn’s private archive, which contains extensive and previously inaccessible sources, On trial provides an in-depth look at the early days of industry-sponsored clinical research. The book examines how the clinic, patients, physicians, nurses, corporations, and authorities interacted in drug testing. It historicises the trials and situates them within their changing framework conditions. Which people and institutions were involved, and who knew what? How were substances tested, and which patients were affected? According to which patterns were the drugs administered? When did which values, guidelines, and standards apply, and what role did they play in practice? In pursuing these questions, the book reconstructs the history of clinical trials from 1940 to 1980 and locates the Swiss example in the period’s landscape of experimentation, not only meticulously tracing the specific practices at Münsterlingen but also telling a larger story about the changing history of clinical trials.