Objectives: This study examined the longitudinal structural stability of a subjective quality of life measure in an ethnically diverse sample of 331 adults with schizophrenia. Methods: Participants completed the Satisfaction With Life (SWL) scale at entry to community-based mental health services and again at 6 and 12 months. Five types of measurement invariance were tested using a series of multiple-group confirmatory factor analyses. Results: All five types of longitudinal invariance were supported. Conclusions: These findings offer strong support for the validity of the SWL scale as a tool for research or for clinical purposes to assess the effectiveness of interventions over time. Implications for use of the SWL scale in evidence-based social work practice are discussed. (Contains 3 tables.)