Drama therapy-based assessment tools are needed to evaluate client progress, create treatment plans, and support research. This paper will address developments and application of role playing assessments with adults diagnosed with intellectual delays. By using a historical analysis approach, this research aims to chronicle significant themes in psychological testing and explore implications for current drama therapy role play assessment. Developments in test construction, rating scales, testing errors, reliability and validity are analyzed within three role play assessments that are relevant to drama therapy researchers.