Few occupational therapy tools exist that evaluate play totally and systematically. The purpose of this study was to examine the Play History Interview and establish its value as a scientific clinical tool. The parents of 15 disabled and 15 nondisabled children between the ages of 1 and 7½ years were interviewed about their children’s play behaviors using the Play History Interview. Children were rated on an ordinal scale according to the criteria outlined on the Play History Chart and Taxonomy for Diagnosis. Interrater and test-retest reliabilities were determined by two independent raters. The scores from the Play History and Minnesota Child Development Inventory were correlated to examine concurrent validity of the Play History. Content validity was studied via a literature review. Significant results suggest that the Play History is a reliable and valid interview in occupational therapy for assessing children’s play behavior.