International medical graduates (IMGs) consistently represent approximately one fourth of both the physician workforce and the graduate medical education (GME) population of the United States. To enter into accredited US GME programs, IMGs must be certified by the Educational Commission for Foreign Medical Graduates (ECFMG). Changes in the number and characteristics of those seeking certification directly affect the GME population and the future physician workforce in the United States. In July 1998, in response to concerns that IMGs might be lacking in basic clinical skills (eg, history taking, physical examinations, communicating with patients in spoken English), the ECFMG initiated a requirement that IMGs pass a clinical skills assessment (CSA) to achieve ECFMG certification. In this study we examined the pool of IMGs seeking certification, using databases reporting on all individuals beginning the certification process from 1995 through 2001. For this period, we found that the number of IMG candidates taking the Step 1 examination decreased by 45.5% (36,983 vs 16,828), and the number of IMGs registered to take Step 2 decreased by 38.1% (31 751 vs 12 122). The number of ECFMG certificates issued annually decreased, from a range of 9000 to 12,000 (1995-1998) to fewer than 6000 (1999-2001). Although the number of IMGs annually seeking and receiving certification has decreased, the quality of the applicants appears to have improved and the number of IMGs certified annually continues to adequately fill GME positions not taken by US medical graduates.