The Breast and Cervical Cancer Prevention and Treatment Act of 2000 (BCCPTA) allows states the option of extending Medicaid eligibility to women diagnosed with breast or cervical cancer through a large federal screening program that does not include resources for treatment. Using qualitative data from interviews with 22 key informants and other sources, we present an analysis of the history and passage of the BCCPTA as a policy response to a perceived "treatment gap" in a national screening program. The results suggest that organizational policy entrepreneurs-primarily the National Breast Cancer Coalition-constructed an effective problem definition (that the government screening program was "unethical" and "broken") with a viable policy solution (an optional disease-specific Medicaid expansion), and pushed this proposal through a policy window opened by a budget surplus and an election year in which women's health issues had broad bipartisan appeal.