Program evaluations are increasingly assessing the impact of treatment delivery and program processes on outcomes. The current study examined the effects of program fidelity, measured across various dimensions, and relationship quality on behavior change and knowledge gained outcomes in 241 middle and high school students who were participating in Expect Respect, an evidence-based dating violence prevention program. Cross-level, hierarchical linear modeling (HLM) analyses found that program fidelity was not a significant predictor of participant outcomes. However, main effects for relationship quality were present for the knowledge gained outcome measure. Subsequent cross-level interactions provided further support for the importance of relationship quality in prevention program outcomes.