This article explores the impact of the Nuremberg Code on post-Second World War research ethics in Britain. Against the background of the Nuremberg Medical Trial, the Code received international endorsement, but how much did its ethical percepts influence actual research? This paper shows that, despite British involvement in the formulation of the Code, the experience of war-time and changing career structures were more influential in shaping the approach of investigators to their subjects. Where medical debates ensued, primarily over controversial research practices at the British Postgraduate Medical School, Hammersmith Hospital, they were set in the context of a much older division between 'bedside' and 'scientific' medicine. But whatever differences there may have been between those physicians who advocated research and those who questioned its use and ethical basis, most clung to the paternalist assumption that it was the doctor's place to decide what was best for his patients. Faced with rising public and medical criticism of contemporary research practices, the medical élite of the 1960s and 1970s safeguarded the reputation of the profession and medical control of research by negotiating new voluntary codes. In a similar move, their predecessors had helped to negotiate the Nuremberg Code in anticipation of public criticism of experimentation arising from the Nuremberg Medical Trial.