This study outlines the development of a multidimensional measure of collective efficacy (CE) for netball using polytomous item response theory, confirmatory factor analysis, and multilevel confirmatory factor analysis (MLCFA). Items were written to fit into six subscales following the suggestions by Paskevich, Brawley, Dorsch, and Widmeyer, (1999). The sample consisted of 537 females in 56 teams. The results showed that at the lower end of the response scale, options were not all endorsed. A six-factor correlated solution was the best-fitting model. MLCFA further produced good model data fit. The results demonstrate that the items and their underlying factor structure are grounded at both the individual and team level, with factor loadings at the team level suggesting the CE items to be a strong measure of team CE. Correlations between the CE measure and the Group Environment Questionnaire provide evidence for the validity of the CE measure.