The purpose of this paper is to explore specialty selection and factors affecting medical students' choices in the era after the implementation of National Health Insurance in Taiwan. From June 1997 to May 1998, a questionnaire was administered to 123 medical students undertaking their rotation internship. The results of 79 respondents showed that the top three options selected by medical students were internal medicine, surgery, and dermatology. Related factors affecting their specialty selection were remuneration for practicing this specialty, expectations of family and significant others, experience during their internship, and personal considerations. It is suggested that, for future medical manpower planning and execution in this country, integrating the influences of the national health insurance program and societal health policy should be considered and examined.