The introduction of the 'Medical Treatment Contract Act' in the Netherlands 5 years ago, established some major rights and duties of both patients and members of the medical profession. The aim of this study was to assess Dutch dentists' knowledge, attitudes and self-efficacy with regard to several topics of this act. A questionnaire was sent to 806 dental practitioners; 41.6% of them responded. Results show that dentists are well informed about some of the most important topics of this law, such as the requirement to obtain the patient's consent to major dental treatments. The results concerning their attitude and self-efficacy, however, are less positive. A majority of the respondents believe that the principle of informed consent will lead to a commercialization of the dentist-patient relation. Also, fear for legal procedures and difficulty with what patients must be informed about appears present. It is concluded that improvement of the implementation of the requirements of this legislation in dental practice requires both a change in attitude and an enhancement of the communicative skills of dentists. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.