<p>While treatment adherence is often considered necessary for optimal clinical outcomes, adherence to evidence-based practices (EBPs) may be poorer in usual care (UC) than in research settings. Practical, accurate adherence monitoring tools may enhance EBP delivery in UC. We examined the psychometric properties of the Cognitive and Behavioral Therapy Adherence Measure (CBTAM), a multi-informant (provider, caregiver, youth) measure of provider adherence to the core components of cognitive and behavioral therapy (CBT) for youth anxiety, depression, and behavior problems. Providers (<i>N</i> = 28, <i>M</i> 29.46 years old; 75% female; 82.14% White; 7.40% Latinx), youths (<i>N</i> = 46, <i>M </i>11.34 years old, 54.35% male; 58.70% White; 6.52% Latinx) and their caregivers (<i>N</i> = 41, <i>M</i> 42.63 years old; 92.68% female; 73.17% White; 9.76% Latinx) rated provider adherence to CBT following each treatment session. Coders rated a subset of treatment sessions using the CBTAM and established observational coding systems for CBT adherence and alliance. Provider, caregiver, and youth CBTAM ratings evidenced full range, but were generally higher than coder ratings. Caregivers and youths were concordant with coders on a few items, while providers were concordant on most items. Provider CBTAM ratings were also correlated with similar items on observational measures, and these correlations were higher than correlations with dissimilar items, demonstrating convergent and discriminant validity. There is initial support for the provider CBTAM as a session-level measure of CBT adherence for common youth mental health problems. Further research is needed to evaluate the CBTAM’s reliability and clinical utility in community settings.&#xa0;</p>