Objectives: The Activity Support Scale (ACTS) was expanded for use with African American families. Its factorial invariance and internal reliability were examined for non-Hispanic white and African American parents. Methods: The ACTS was modified to improve its applicability to African American families based on information from five focus groups with 27 African American parents of elementary school-aged children. Between 2006 and 2008, the revised scale was administered to 119 African American and 117 non-Hispanic white parents in northeastern NY and Alabama. Its factorial invariance across race/ethnicity and internal consistency were examined. Results: Factor analysis of the revised scale, the Activity Support Scale for Multiple Groups (ACTS-MG), identified four parenting factors in white and African American parents including logistic support, modeling, use of community resources to promote physical activity (PA), and restriction of sedentary behaviors. Results supported the scale's internal reliability and factorial invariance across race/ethnicity. Conclusion: The ACTS-MG is appropriate for use with non-Hispanic white and African American families and will enable the extension of current research with white families to the examination of strategies supporting PA in African American families. Additional psychometric work with the ACTS-MG is encouraged. © 2010 Elsevier Inc.