Background: Sleep disturbance, particularly insomnia, is prevalent in cancer patients undergoing chemotherapy. Our clinically-based Brief Behavioral Therapy for Insomnia (BBT) is a new approach for treating symptoms during cancer care and can be used as a model for other behavioral interventions during medical treatment. Our design allows us to capture patients just as they are developing insomnia symptoms, but before their problems become chronic and require more intensive intervention. The innovation of our behavioral intervention is that we can deliver it in tandem with patients' biomedical treatments, by their bedside, which is a focal point of translational behavioral research, significantly minimizing patient burden. BBT is a brief (3 hrs over 6 weeks), feasible and acceptable intervention that has shown promise in reducing insomnia and cancer-related side effects and in improving circadian rhythms at a single site (Stanford Cancer Center). The development and feasibility of BBT was supported through a K award by the NCI. The proposed Phase II RCT is designed to test the feasibility and efficacy of administering BBT in a multicenter community clinical oncology program (CCOP) network. Methods: The proposed study will gather preliminary efficacy data on conducting BBT in 70 breast cancer patients undergoing chemotherapy in 5 community clinics via CCOP network where the intervention will be conducted by trained clinical staff (e.g., clinical research assistants, nurses) rather than clinical psychologists using our manualized intervention. We will examine the impact of BBT primarily on insomnia and secondarily on mood and quality of life. In addition, we would like to examine underlying biological mechanisms: circadian rhythm disruption, autonomic dysfunction and sleep-wake cycles. This project has already received peer review at the NCI and has been approved as a concept and protocol for a multicenter study. This R21 is needed to support the costs for this project that are not already covered under the University of Rochester Cancer Center CCOP Research Base and the individual CCOPs. Given the recent NCI approval, funding via R21 can leverage the existing CCOP resources by providing funds for examination of the potential involvement of dysregulated circadian rhythms (actigraphy) and autonomic tone (heart rate variability) as biological potential mechanisms for any changes in insomnia noted during the intervention.