This article describes the background characteristics, work environments, and job characteristics of the physician assistant profession as they existed in late 1974 and early 1975. Of the 939 physician assistants participating in this study, three-fourths were working in primary care specialties and half were located in communities having fewer than 50,000 persons. Favorable levels of responsibility for patient care, supervisory support, and role acceptance were reported by respondents. The mean income was $14,285. Job opportunities appeared plentiful, but career opportunities were considered by most to be either limited or nonexistent. Physician assistants are providing important additional medical manpower in primary care fields and in smaller communities, but the perceived lack of opportunities for career advancement may prove to be a significant problem for this emerging health profession in the years ahead.