Abstract: Treatment fidelity remains essential for effective dissemination of health interventions, guiding new techniques with operational definitions for real-world settings. Translating the importance of fidelity from research to practical application necessitates the utilization of clinician-based tools and processes that support quality service delivery. This article introduces a self-report instrument to guide provider adherence of a 10-week patient-centered health promotion group for sexual and gender minority veterans: PRIDE in All Who Served (PRIDE). The PRIDE Fidelity Assessment Instrument (PFAI) is a clinician self-report measure designed to capture PRIDE treatment adherence across each of the 10 sessions. The PFAI was provided to 21 PRIDE group facilitators across 13 Veterans Health Administration sites. PFAI utilization was generally high among clinicians, with notable variation. Initial psychometric properties of the instrument revealed high interrater agreement, limited variance, and considerable ceiling effects. Total fidelity scores suggest a consistently high degree of treatment fidelity across completed sessions in this sample (adherence ≥ 94%). Our results support the use of pragmatic fidelity measures, like the PFAI, particularly during initial training, implementation support, and early delivery of evidence-based practices like PRIDE. Practical and conceptual challenges to clinician-based self-report fidelity assessment in general are discussed along with recommendations for future investigations and use of the PFAI.