Surveys were mailed to all nurse practitioners (NPs), physician assistants (PAs) and certified nurse midwives (CNMs) registered in California, asking questions about education, labor force participation, specialty, and location and type of practice site, as well as the demographic characteristics of these professionals and their patients. Response rates for each of the three professions (66 percent of 7,341 NPs, 57 percent of 2,938 PAs, and 70 percent of 859 CNMs) were sufficient to provide a broad overview of these professions at the state level but insufficient for analysis of supply in small geographic areas within the state. Major findings of the survey include the following: (1) the numbers of these professionals have grown dramatically over the past decade, with half of each profession completing education in the 1990s; (2) most of these medical care providers are practicing in their fields, and most spend most of their working hours providing direct patient care; (3) the majority of NPs, PAs, and CNMs provide primary care services in a wide variety of settings; (4) these providers care for large numbers of underserved persons; (5) most NPs, PAs, and CNMs are in their 40s and 50s, and most were educated in California; and (6) minority groups are underrepresented in all three professions. (Survey forms are included in this report.) (KC)