This report describes the development of a criterion-referenced proficiency examination for dental auxiliaries that consists of both written and performance tests in each of five areas: chairside assisting, patient education, diagnostic aids, therapeutics, and laboratory procedures. The content outlines of the tests are presented. The formation of the committees and the processes of test planning and test development are described. Checklists were developed for the observers to use in scoring the performance tests. A preliminary field trial of the test was administered to a small sample of dental auxiliaries, and revisions were made to the test and the scoring checklists. The revised tests were then administered to 115 dental assistants or dental hygienists. The development of the scoring formulas for the performance tests was a three-stage process. Inter-observer reliabilities were computed for each subtest, and score distributions were compared for auxiliaries rated adequate with those rated inadequate by the observers. Various methods were used to select recommended pass/fail cutoff scores. Conclusions of the study and recommendations for further development are presented. (Author/CTM)