Based on the premises that strength-based assessment of children and adolescents is an important emerging area, and that additional tools for this purpose are needed, this study details development and validation efforts on a new strength-based assessment: the Social-Emotional Assets and Resilience Scale, parent form (SEARS-P). Following careful development of a comprehensive research prototype assessment, a large and diverse nationwide sample of more than 2,000 ratings of school-age children and adolescents were obtained from their parents and other caregivers. Factor analytic procedures revealed a robust and replicable underlying factor structure, including Self-Regulation/Responsibility, Social Competence, and Empathy factors. The factor scores and total score of the SEARS-P were shown to have strong internal consistency reliability, as well as strong interrater reliability between mother-father pairs who rated the same child. Convergent construct validity of the SEARS-P was established through findings of significant correlations with two established strength-based rating scales for use by parents. Construct validity of the SEARS-P was further bolstered through findings of significant gender differences in scores (with females rated as having higher levels of competency than males), as well as significant differences in scores based on educational disability status. Limitations and future research needs are discussed, as are implications of this study for research and practice with children and families.