Advances in molecular genetics have evolved at such a fast pace that physicians may be bewildered about their clinical translation into patient care. However, genetic counselors, particularly those trained in cancer genetics, have been extremely helpful. The challenge to the physician, however, calls for an understanding of the natural history of hereditary cancer syndromes, which is often reflected in the pedigree. Pedigree/family history information must be compiled in sufficient detail to arrive at the most likely hereditary cancer syndrome diagnosis so that the molecular geneticist can search for the mutation. Finally, the challenge to the clinician is melding this into an accurate diagnosis, in order to provide highly targeted screening and management for high-risk patients. This article is an attempt to crystallize all of these issues in a format that will help physicians-particularly those in the oncology community-to meet this challenge effectively.