This is a report on the treatment fidelity of in-home cognitive-behavioral therapy (CBT) delivered by a sample of clinically trained, master's-level social workers to a group of primarily rural, medically frail older adults as part of the Project to Enhance Aged Rural Living (PEARL) clinical trial. The social workers in this study received brief didactic and experiential CBT training. Audiotaped sessions were randomly selected and evaluated by independent reviewers. Results showed that the social workers adequately delivered CBT as measured by the Cognitive Therapy Scale. Older adult participants also evidenced pre-posttreatment improvements, suggesting that the social workers' delivery of CBT facilitated improvement.