A Scotsman and a graduate of St Andrews University, Professor Michael Rosen spent most of his working life as a consultant anaesthetist in Cardiff where he contributed greatly to the research activities of the associated academic department. In recognition of this the College of Medicine of the University of Wales accorded him the title of Honorary Professor. His clinical interests were many and varied but the greatest was obstetric anaesthesia and analgesia. He developed patient-controlled analgesia (PCA) in this context and with the help of the Department of Medical Physics developed the first commercial PCA machine, the Cardiff Palliator. He also developed the Cardiff valve, an essential 'gadget' in many situations. He was an active medical politician, being successively Secretary, Treasurer and President of the Association of Anaesthetists of Great Britain and Ireland.