The National Health Service Corps: rapid growth and uncertain future.

From inauspicious origins in laudable, but vague, legislation and diffident--even disorganized--implementation, the NHSC has evolved into a major federal program for delivering health care to underserved areas. Tying together the financing of medical education and the delivery of health services for the first time could enable responsiveness to both qualitative and quantitative changes in medical care. But competing demands, within the program and its administration, and in the communities to be served, have made evaluation of the NHSC effort and impact difficult, but all the more necessary for future planning.