This national study of community-based addiction-treatment organizations' (CBOs) implementation of evidence-based practices explored CBO Program Directors' (n = 296) and clinical staff (n = 518) attitudes about the usefulness of science-based addiction treatment. Through multivariable regression modeling, the study identified that identical factors were associated with directors, and staff attitudes about the usefulness of science-based addiction treatment. For both directors and staff working in an organization that was affiliated with a research institution, working in an organization with better internet technology (measured through TCU-ORC scores) and having higher levels of education were all significantly associated with having more positive attitudes regarding science-based addiction treatment. Implications: government policy that promotes the hiring of addiction treatment clinical staff with professional degrees and encourages the development of linkages between addiction treatment researchers and treatment staff may positively impact attitudes and use of evidence-based addiction treatment practices (EBPs) in CBOs. (Contains 5 tables.)