The testing of psychosocial interventions in a clinical trial poses many challenges to maintaining a rigorous experimental protocol and to delivering the interventions uniformly throughout the project. These challenges directly affect the reported effectiveness of psychosocial interventions. In this article, the authors describe the treatment fidelity plan developed by an interdisciplinary research team from recreational therapy and nursing for implementing recreational activities during a clinical trial funded by the National Institute of Nursing Research. The trial tests the efficacy of activities for responding to the behavioral symptoms of dementia. The authors report treatment fidelity strategies to allow comparison of their intervention with that of other studies, to improve effect size in similar studies, and to facilitate replication and translation of this work into clinical practice.