In this commentary, the issue of fidelity assessment is addressed as it relates to Strain and Bovey's article (2011). Four reasons are provided for measuring fidelity in intervention studies. Measuring fidelity (a) potentially allows investigators to document the findings were not due to the lack of fidelity in a study; (b) presents information about how transportable interventions are to the real world; (c) provides information for replication studies; and (d) sheds light on the nature of children's experiences in the study.