Nowadays, partly due to legislation, decision-making competence is playing an ever-increasing role in psychiatry. So far, however, there are no clear criteria for evaluating the actual competence of the procedure.<br/> AIM: To develop a relational ethical model, including criteria and methodology, which can be used to assess and enhance decision-making competence mainly from a relational and ethical perspective.<br/> METHOD: Combination of a review of the literature and ethical reflection. First of all, a limited study was made of the literature relating to the concept of and criteria for decision-making competence. On the basis of the literature and relational ethical reflection, ten criteria were developed for decision-making competence and a method was devised for assessing the procedure.<br/> RESULTS: The criteria that have to be satisfied can be summarised as follows: the persons involved must understand the information, and must be able to apply it to their own situation. They must be able to gain insight into their own situation and be able to weigh up the available options, and be able to estimate consequences for themselves, as well as for others. They must be able to motivate choices in a sensible and comprehensible manner without being subject to coercive influences coming from internal and external sources. Participants' choices should be motivated on the basis of their own personal values. The decision-making competence is assessed and enhanced by giving a score to the individual criteria and by making an overall evaluation. This is achieved by a dialogue including all the persons involved: the care seeker (as far as possible), close relatives and the care-providers.<br/> CONCLUSION: The persons involved can attain greater objectivity by exchanging views orally on the ten proposed criteria for decision-making competence.