the period covered in this chapter offers an extremely difficult problem to the historian, not only because it is so close to us, but also because progress has been so rapid and in some regards so revolutionary in all fields of medical science that it is almost impossible to form a synthetic judgment of all the factors that played an important part in the evolution of medicine. There have been in recent times several attempts, especially in the United States, to describe the medical historical events in the last fifty years, taking into consideration the influence that economic changes had on the development of medicine. Increasing understanding of the importance of medical history is proved by the fact that in almost all recent medical books devoted to different branches of medicine the introduction deals with a historical outlook. We think, however, that the evolution of contemporary medicine can be best understood in connection with the general history of medicine of the past. This may offer the opportunity to study not only the relation between events and the doctrines that have prevailed at different times, but also the gradual development of medical thought and of new concepts of the duties and rights of the physician and the part that he has to play.