Objective: Research-supported treatments (RSTs) are considered the gold standard of client care. Investigating how to best implement and sustain RSTs in real-world practice is important. The present study addressed a gap in the literature concerning the relative contribution of RSTs and culture and climate to client outcomes in community-based child welfare services. Method: Using data collected from 55 programs within a single, large child and family human services agency, this study examined whether programs with less productive cultures and climates were able to implement RSTs and realize successful client outcomes. Results: In contrast to findings of the existing literature, programs with less productive culture and climate scores implemented RSTs and yielded successful client outcomes. Conclusions: Given the choice between maltreated children being treated in a program with good culture and climate or one that provides RSTs, the best selection for improved outcomes would be the one offering RSTs.