Objectives To investigate high school cheating experiences and attitudes towards academic misconduct of freshmen at all four medical schools in Croatia, as a post-communist country in transition, with intention of raising awareness of academic (dis)honesty. Design and method Students were given an anonymous questionnaire containing 22 questions on the atmosphere of integrity at their high school, self-reported educational dishonesty, their evaluation of cheating behaviour, and on their expectations about the atmosphere of integrity at their university. Setting All schools of medicine (...) of Croatian universities (Zagreb, Rijeka, Split and Osijek). Main measures Descriptive statistics and differences in students' self-reported educational dishonesty, perception of cheating behaviour, and perception of the high school integrity atmosphere. Results Of the 761 freshmen attending the four medical schools, 508 (67%) completed the questionnaire: 481 Croatian and 27 international students. Of the Croatian respondents, almost all (>99%) self-reported engaging in at least one behaviour of educational dishonesty, and 78% of respondents admitted to having frequently cheated in at least one form of assessed academic misconduct. Only three students admitted to having reported another student for cheating. For most of the questions, there was no significant difference in the responses among Croatian students. However, significant differences were found in most responses between Croatian students and their international counterparts, who were significantly less likely to engage in dishonest behaviours. No individual factor was found to correlate with the incidence of self-admitted dishonest behaviour. Frequent cheaters evaluated academic dishonesty significantly more leniently than those who did not cheat. Conclusion Academic dishonesty of university students does not begin in higher education; students come to medical schools ready to cheat. (shrink)