The Breakthrough RESEARCH business case for investing in social and behavior change (SBC) for malaria modeled SBC cost-effectiveness of malaria SBC in Tanzania by combining evidence on the cost and effectiveness of SBC for malaria-related health behaviors with country-specific data on the current malaria context and an estimated five-year investment scenario based on national planning and implementation reports from the United States Agency for International Development and the Global Fund. This brief provides a summary of the findings.