A follow-up survey of 1,087 physicians who had graduated from the University of California, San Francisco, School of Medicine from 1951 through 1971 was completed in 1977. A total of 307 (28.2 percent) of these persons were found to have left California. Comparison of the 307 who left with the 780 who remained showed only slight and statistically insignificant differences on most variables, such as sex, academic performance in premedical and medical education, educational level and social class of parents, age at entry into medical school, ratings by admissions interviewers, choice of specialty and a wide variety of personality inventory measures. Among the variables that did differentiate were place of birth, location and prestige of premedical college, preferences for subjects in the sciences and the humanities, and the Medical College Admission Test (MCAT) scores for quantitative ability and general information. However, attempts to combine these individual differentiators into clusters or equations from which to forecast emigration from California were unsuccessful.