Cancer vaccines are emerging as important tools for cancer treatment and prevention. Unfortunately, the cohorts that ultimately will benefit most from the vaccines, those at elevated risk for cancer, are likely to be stressed. Chronic stress can impair immune function, including immune response to vaccines. An inadequate response to vaccines can weaken their protective effect. Women at elevated risk for breast cancer can experience significant levels of distress and have associated immune function decrements. Interventions to treat distress-related immune decrements among these women are needed because these women will be among the first candidates for breast cancer vaccines. In theory, stress-management interventions should improve immune function and response to vaccines; however, the findings to date are mixed. The proposed investigation will conduct an exploratory randomized clinical trial to collect preliminary data on the efficacy of a cognitive behavioral stress management (CBSM) group intervention among women who are at elevated risk for breast cancer because of family history and who are reporting elevated levels of distress. Study outcomes will include antibody and cellular immune response to hepatitis A vaccine and self-reported distress.