Although the importance of dentist-patient communication is generally recognized, the dental literature does not specify what interpersonal behaviors can be used as a basis for evaluating dental students' communication skills. A set of behaviors based on clinical observations is described, and an evaluation of 25 senior students' behavioral skills is presented. Students often did not: (1) spend much time orienting patients before beginning treatment; (2) update medical histories; (3) ask patients if they had any questions before beginning treatment; (4) explain the operation and use of equipment; (5) forewarn patients about uncomfortable procedures; (6) attend to signs of patient discomfort; (7) reinforce praiseworthy patient behavior; (8) caution patients about numbness, chewing, and sensitivity; (9) thank patients for their time; and (10) use leading/motivating questions. There is a need to provide students with systematic feedback on their interpersonal behaviors.