The overall goal of this study is to determine the effectiveness of the remote-support weight loss intervention of the POWER study, designated POWER-remote, in women with early breast cancer who are overweight or obese, and to assess the effects of weight loss of ≥5% body weight at 6 months and on biomarkers associated with obesity, inflammation, and breast cancer. The data will be used to implement a clinical intervention available to all overweight and obese women with breast cancer, and to design definitive studies assessing the impact of weight loss and biomarker modulation on risk of recurrent disease or development of new primary breast cancers.