AIM: To develop leaflets that would promote and increase tissue and organ donation and to test their persuasive value. METHOD: The study was carried out in two parts. In Study 1, we assessed attitudes, knowledge, and intentions about tissue and organ donation of 200 randomly chosen persons from the population of the capital of Croatia, Zagreb, as well as of 108 health professionals in different hospitals in Zagreb. We also assessed the willingness of health care professionals to ask their patients whether they were willing to donate their tissue and/or organs. Dependent variables in this study were attitudes, knowledge, and intentions. On the basis of attitude and knowledge analyses, two types of tissue and organ donation promotional leaflet were developed: one intended for the community sample and the other for health professionals. The leaflets were used as independent variable. In Study 2, performed a year later, the leaflets were presented to another group of 184 persons from Zagreb population and 50 health professionals. We compared attitudes, knowledge, and intentions of community sample and health professionals presented with leaflets vs those not presented with leaflets, and assessed the persuasive power of the two types of promotional material developed. RESULT: The community sample presented with the leaflet in Study 2 showed significantly more positive attitudes towards organ donation when compared with the group not presented with a leaflet in Study 1 (t=2.26; p=0.025), but there was no significant improvement in attitudes towards tissue donation or intention to either donate or receive tissues and organs for transplantation. For health professionals, the Study 2 group presented with a leaflet showed a tendency toward less positive attitudes but significantly more positive intention than those in Study 1 not presented with a leaflet to donate bone marrow (t=2.39; p=0.021) and one's own organs (t=2.24; p<0.027), and to ask others about blood donation (t=2.1; p=0.037). CONCLUSION: Presentation of leaflets succeeded in producing a tendency toward more positive attitudes and intentions toward tissue and organ donation. Still, a single presentation is clearly insufficient to produce significant change in all variables - attitudes, knowledge, and intentions.