In an attempt to explore the linkages between corruption surveys, underreporting corruption experiences and causes of reluctance to report corruption, this paper provides insight into solutions applied to mitigate the underreporting risks in surveying corruption experiences in Croatia. Based on the “Survey on use of public services and public integrity” conducted in Croatia in the summer of 2010, the issue of underreporting corruption is assessed here with a two-fold approach. The study first discusses the various aspects of the survey methodology applied, where the main concerns were the willingness of respondents to report corruption and their perceptions regarding risk of personal data misuse. Potential reluctance to admit involvement in corruption as a criminal act might be driven by a fear of subsequent surveillance or investigation. Further, we investigate the concerns expressed by respondents regarding the misuse of data, in particular with regard to protecting anonymity. The other issue arises from the direct survey results and refers to citizens’ attitudes and reasons for (not) reporting crime to official institutions. The analysis particularly focuses on reporting corruption experiences, both formally and informally. The results of the survey show a very high level of citizens’ opportunism and lack of public trust in institutions that might impede anti-corruption efforts in Croatia.