year. As say they were distributed among hospitals treating fifty to a hundred patients a year. So that was myfirst objective in going. I didn't want to be the head of this, but I wanted to see it created. To makea long story short, and to pass overa lot of political shenanigans, that has come to pass and there now is something called the Joint Center for Radiation Therapy in the Longwood Avenue area. It may be the largest departmentof radiation therapy in the United States. They treat something like four thousand patients a year. Certainly far more than three thousand. I regard that as my chief contribution in this field. Then the other thing was to create a laboratory of radiological sciences, and I think I did the right thing there by establishing groups for diagnosis, for therapy, for nuclear medicine, and for my own workin biology. Each group wasresponsiblefor itself; they were not under me as a laboratory director. My own experimental work, in collaboration with Dr. Roger Melvold, confirmed that previously done with Dr. Bailey, that there were not any transmissible x-ray induced mutations in the mouse histocompatibilty system. I should also add that this work led me to have a general interest in genetics work at the Medical School. Harvard at that time did not have a department devoted to medical genetics. Instead there was established at that time a loose confederation of workers from several departments in several hospitals called the Center for Human Genetics, of which I served as the initial Director for some years. [4. Biology and Physics] Kohn's Edited Insert: A project that took a great deal of my time end energy during the period of 1975-1979, was the work of the National Academy of Science Committee on Nuclear and Alternative Energy Systems. There were about a half-dozen people on the Committee and this book is the Committee's report, issued in 1980. 16