Purpose: This study examines the psychometric properties of the Teamwork Scale for Youth, an assessment designed to measure youths' perceptions of their teamwork competency. Methods: The Teamwork Scale for Youth was administered to a sample of 460 youths. Confirmatory factor analyses examined the factor structure and measurement invariance of the scale across time. Correlations between teamwork and perceived social competence and commitment scores were also examined. Results: The revised 8-item Teamwork Scale for Youth was found to demonstrate acceptable factorial validity and measurement invariance across time. Additionally, strong reliability and concurrent and predictive validity of the scale were established. Discussion: The Teamwork Scale for Youth is a brief, easily administered, psychometrically sound tool that can be used with confidence in social work research and practice.