Fidelity of implementation (FOI), which concerns whether a program is delivered as planned (Durlak & DuPre, 2008; Nelson et al., 2010), has become an increased concern within the context of impact evaluations, specifically in educational settings. The inclusion of measures of fidelity is theorized to increase the internal validity of evaluation findings while also providing stakeholders with important information concerning implementation. The goal of this paper is to provide examples of how evaluators in educational settings have applied existing frameworks to measuring FOI. The general challenges brought forth by these approaches are presented, along with the potential unintended consequences of framing fidelity in a narrow manner. Finally, an alternative approach to measuring implementation within the context of education is offered that more appropriately accommodates diversity in implementation.