Assessment of social and emotional learning (SEL) in young children is critical to understanding developmental progress and informing care and instruction. The current study investigated the development of a behavior rating scale designed to measure SEL skills in preschool-age children. The primary objective of this study was to investigate the development of a new strength-based assessment prototype, the Social-Emotional Assets and Resiliency Scale for Preschool (SEARS-Pre). Items for the SEARS-Pre were developed based on a review of literature and existing measures and evaluated by a content validation panel of ten experts in the field. Following the content validation and revision process, local preschools were recruited to pilot the final SEARS-Pre measure. Eighteen instructors from three preschool programs in Oregon participated and completed a total of 94 SEARS-Pre rating forms for students in their classrooms. Results from an exploratory factor analysis suggested three factors: Self-regulation/Social competence; 2) Emotion knowledge/Expression; and 3) Empathy/Responsibility. The scale demonstrated strong internal consistency, with alpha values of 0.95 for Factor 1 (Self-Regulation/Social Competence), 0.92 for Factor 2 (Emotion Knowledge/Expression), 0.90 for Factor 3 (Empathy/Responsibility), and 0.97 for the total score (all three factors). [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]