Pancreatic cancer is the fourth leading cause of cancer death in both men and women in the United States and will be responsible for an estimated 28,900 deaths in 2001. Relatively little is known of its etiology, and the only well-established risk factor is cigarette smoking. Studies over the past 3 decades have shown that 4%-16% of patients with pancreatic cancer have a family history of the disease. A small fraction of this aggregation can be accounted for in inherited cancer syndromes, including familial atypical multiple-mole melanoma, Peutz-Jeghers syndrome, hereditary breast-ovarian cancer, hereditary pancreatitis, and hereditary nonpolyposis colorectal cancer. These syndromes arise as a result of germline mutations in the BRCA2, pl6 (familial atypical multiple-mole melanoma), mismatch repair (hereditary nonpolyposis colorectal cancer), and STK11 (Peutz-Jeghers syndrome) genes. In addition, hereditary plays a role in predisposing certain patients with apparently sporadic pancreatic cancer. Many patients with pancreatic cancers caused by a germline mutation in a cancer-causing gene do not have a pedigree that is suggestive of a familial cancer syndrome. A recent prospective analysis of the pedigrees in the National Familial Pancreatic Tumor Registry found that individuals with a family history of pancreatic cancer in multiple first-degree relatives have a high risk of pancreatic cancer themselves. The identification of such high-risk individuals will help clinicians target screening programs and develop preventive interventions with the hope of reducing the mortality of pancreatic cancer in these families.