Most senior consultant anaesthetists will be able to recall times during their early careers when anaesthetic assistance in theatre could be described at best as rudimentary. There was often willing help for the anaesthetists but it was provided largely by those whose training, through no fault of their own, was negligible. It is true, of course, that the early anaesthetic assistants did not have to contend with the complex range of anaesthetic equipment that is now available, and it comes as a surprise to many, for instance, to learn that the use of pulse oximetry did not become routine in the operating theatre until the late 1980s. That chapters in this book include accounts of topics such as perioperative myocardial infarction, mechanical ventilation and awareness during anaesthesia indicates just how much progress has been made since those often unsatisfactory times. Further chapters on the development of a personal portfolio and on the implications of professional accountability also serve notice that the era of the Anaesthetic Practitioner is nigh: an era that the ODAs of twenty-five years ago could never have envisaged. The modern reality, finally, is that the theatre orderly of two or more decades ago is now a degree student, ODP, of whom is required an understanding of the basic sciences which underpin the safe practice of sophisticated modern anaesthesia.