Research on the evaluation of World Wide Web sites has already begun, but it is proceeding at a slow rate. The main reasons for this are the attempt to adapt existing methodologies to the particularities of the Web, the individual structure of Webs sites, and the issue of finding the appropriate evaluators. This study addresses these points and suggests a heuristic approach to the evaluation of Web sites. In the study, the evaluators were trained in the particularities of the heuristic evaluation in its classic form as well as in its Web-adapted form. Next, the researchers used Web-adapted heuristics, found in relative literature, and clarified them to the evaluators. Finally, the evaluators were involved in a real evaluation of five Web sites, and they wrote down their comments on questionnaires. The results confirmed two known conclusions: that the method is applicable to the Web; and that the prior evaluators' expertise is of great importance. It was also concluded that it is possible to augment this expertise in a short way, so that the evaluators have an increased performance during the evaluation as well. The main conclusion was that the heuristic list used performed inadequately, but the trend of the evaluators following a somewhat similar mode of thinking was noted, thus providing a way to adapt these heuristics in a more holistic approach to the Web. (Contains 27 references.) (Author/MES)