Breast cancer survivors are living longer and may be living with many symptoms incurred from the disease and its treatment. Survivors from 1 to 2 years off treatment report continued fatigue, depression, pain and sleep disturbances (Kenefick 2006; Byar et al. 2006). Patients often present with several concurrent symptoms (Dodd et al. 2001; Esper and Heidrich 2005). It is believed that symptoms tend to cluster together (two or more concurrent symptoms related to one another and independent of other symptoms) and may have natural associations, similar shared pathways and underlying mechanisms (Barsevick 2007). Currently, little is known about how symptoms cluster in breast cancer survivors after treatment, underlying mechanisms, and if interventions can influence multiple symptoms simultaneously (Lee et al. 2004; Cleeland et al. 2003). Very few studies have tested interventions during post-treatment survivorship (Cimprich et al. 2005; Mishel et al. 2005; Stanton et al. 2005; Scheier et al. 2005). Mindfulness-Based Stress Reduction (MBSR), a standardized form of meditation and yoga, has been shown to be effective in reducing anxiety, depression and stress in patients with chronic pain (Kabat-Zinn et al. 1992; Miller et al. 1995; Teasdale et al. 2000; Kabat-Zinn et al. 1985). Preliminary results from 2 pilot studies conducted by our research team provide support that MBSR for breast cancer survivors may be effective in markedly reducing symptoms, increasing quality of life, and decreasing fears of recurrence (Lengacher et al. 2009; Lengacher et al. 2006). This proposed study builds on our preliminary data of the MBSR Breast Cancer Program (BC) to reduce stress, biological markers of the stress response (pro-inflammatory cytokines) and improve physical, and psychological symptoms and quality of life in breast cancer survivors.