Rapid advances in our ability to test persons presymptomatically for genetic diseases have generated increasing concern that genetic information will be abused by insurance companies. Reasoning that the insurance companies may have the strongest interest in using genetic data and that the medical directors of those companies with responsibility for rating applicants would be a good source of information on the use of such data, we conducted a large survey of medical directors of North American life insurance companies. We received responses from 27 medical directors. Our results suggest that (1) few insurers perform genetic tests on applicants, but most are interested in accessing genetic test information about applicants that already exists; (2) the degree of insurers' interest in using genetic test results may depend on the face amount of the policy applied for and on the specificity and sensitivity of the test; (3) many companies employ underwriting guidelines with respect to certain genetic conditions but may not always have specific actuarial data in house to support their rating decisions; (4) a considerable degree of subjectivity is involved in most insurers' rating decisions; and (5) some of the medical directors who responded to our survey are not fully informed about certain basic principles of medical genetics.