The development of the EURACT (European Academy of Teachers in General Practice) Educational Agenda helped many family medicine departments in development of clerkship and the aims and objectives of family medicine teaching. Our aims were to develop and validate a tool for assessment of students' attitudes towards family medicine and to evaluate the impact of the clerkship on students' attitudes regarding the competences of family doctor. In the pilot study, experienced family doctors were asked to describe their attitudes towards family medicine by using the Educational Agenda as a template for brainstorming. The statements were paraphrased and developed into a 164-items questionnaire, which was administered to 176 final-year students in academic year 2007/08. The third phase consisted of development of a final tool using statistical analysis, which resulted in the 60-items questionnaire in six domains which was used for the evaluation of students' attitudes. At the beginning of the clerkship, person-centred care and holistic approach scored lower than the other competences. Students' attitudes regarding the competences at the end of 7 weeks clerkship in family medicine were more positive, with exception of the competence regarding primary care management. The students who named family medicine as his or her future career choice, found holistic approach as more important than the students who did not name it as their future career. With the decision tree, which included students' attitudes to the competences of family medicine, we can successfully predict the future career choice in family medicine in 93.5% of the students. This study reports on the first attempt to develop a valid and reliable tool for measuring attitudes towards family medicine based on EURACT Educational Agenda. The questionnaire could be used for evaluating changes of students' attitudes in undergraduate curricula and for prediction of students' preferences regarding their future professional career in family medicine.