1. Abstract Our long-term goal is to decrease the weight-related breast cancer and cardiovascular disease mortality among African American breast cancer survivors. In the R01 application, our overall objective is to determine the real- world effectiveness of the materials developed during the R34 – Take off Pounds Sensibly (TOPS) for African American Breast Cancer Survivors – on weight. Our central hypothesis is that TOPS for African American Breast Cancer Survivors will help participants achieve significant weight loss. This hypothesis is based on the following: 1) our preliminary data show that TOPS can help women achieve and maintain significant weight loss; 2) the materials from the Moving Forward and Lifestyle, Exercise and Nutrition (LEAN) studies, which we are adapting to add to the TOPS program to create TOPS for African American Breast Cancer Survivors, have been shown to help breast cancer survivors achieve significant weight loss; and 3) the additional materials will be approved by African American breast cancer survivors who have already participated in the TOPS program. To plan to test the central hypothesis, we will pursue the following specific aims in the R34: 1) Adapt materials from Moving Forward and LEAN with the input of African American breast cancer survivors; 2) Conduct a pilot test of the new materials and study processes where we a) recruit participants through the electronic health record; b) convert from a peer-led to a dietitian-led intervention for the initiation phase; c) transition participants to TOPS chapters in the community for the maintenance phase; and d) collect data in a virtual setting and in the community. The proposed research is innovative because for the following reasons: 1) it combines efficacious weight management programs developed at academic institutions with a low-cost community-based program with national infrastructure; 2) it transitions participants to a maintenance phase in their communities where they can receive ongoing support indefinitely; 3) it collects data via Bluetooth scales and at LabCorp sites in their communities; and 4) to our knowledge, this is the first study to test a sustainable weight management intervention for African American breast cancer survivors. The proposed research is significant because it will develop the evidence base for a scalable weight loss intervention among African American breast cancer survivors – a population with poor breast cancer and cardiovascular disease outcomes. The rationale for this project is that the successful completion is expected to provide evidence that a community-based, weight loss program with a national infrastructure can help African American breast cancer survivors manage their weight, which may decrease their breast cancer recurrence and mortality; reduce CVD morbidity and mortality; and improve their quality of life.