Assessment for hereditary susceptibility to cancer is considered standard of care, as it impacts not only a clinician's understanding of cancer causation but also options for prevention and treatment. The roots of our current knowledge about hereditary cancer syndromes can be traced to early reports of families with striking cancer histories. The purpose of this article is to review the historical timeline of the two most commonly assessed hereditary cancer syndromes, hereditary breast and ovarian cancer (HBOC) and Lynch syndrome (LS). While many individuals identified with these syndromes today come from families similar to those seen in the early historical reports, our understanding of these syndromes, their expression and penetrance, has evolved over the years. In addition, the increased utilization of broad multi-gene panels continues to add to the complexity of defining associated phenotypes. These findings can lead to challenges with translating results to clinical management for patients and families, but also provide an opportunity to continue to gain understanding of the genetic underpinnings of cancer etiology.