AbstractAn explosion in the number of trained medical oncologists has led to concern that an overproduction will occur. A survey of 154 medical oncology training programs revealed 767 current trainees—316 first year, 307 second year, and 144 third year. Seventeen programs contained 301 persons (38.5%). After the 1985 certifying examination, 3,659 oncologists were certified. With approximately 750 eligible candidates for each examination, and assuming a 75% pass rate, by 1989 there will be 4,779 certified medical oncologists. By 1990, there will be no deficiency of clinical medical oncologists, but there appears to be a lack of academic oncologists. In order to assure the quality goals of oncology, and in an attempt to meet an adequate supply of medical oncologists, a position statement has been published by the American Society of Clinical Oncology. To avoid an overproduction of medical oncologists, an ongoing assessment of the number needed is warranted.