Leon Hammer, M.D., is a graduate of Cornell University, Cornell University Medical College, and the William A. White Institute of Psychiatry, Psychoanalysis, and Psychology. Until 1971 he practiced psychiatry. He has directed a child guidance clinic and drug abuse council on Long Island, taught at Adelphi University, and served as psychiatric consultant in both medical and educational contexts. After working with Fritz Perls and Alexander Lowen for over eight years, he began a serious study of Chinese medicine in 1971, first in England and subsequently in Beijing and New York (where, since 1974, he has worked under Dr. John Shen). He has practiced for many years in Eastern Long Island and currently maintains his office in Saratoga Springs, New York. His articles on a range of medical and psychological issues have been widely published, and he continues to lecture and teach.