Sleep deficiency is common and distressing for women with breast cancer throughout the care continuum. This article describes the scope and quality of evidence related to exercise interventions to improve sleep in women with breast cancer. Fifteen studies met the criteria and 12 were judged to be excellent quality. The most frequent intervention was walking, primarily during the time of chemotherapy. Eleven studies reported postintervention improvement in sleep deficiency. Most yoga, qigong, and dance intervention studies reported no differences between groups. Emerging evidence exists for the effectiveness of aerobic exercise to improve various sleep outcomes in women with breast cancer. Keywords: Breast cancer; Exercise; Intervention; Sleep deficiency; Systematic review.