Objective: In turn, personal and behavioural characteristics found in drivers who use seat-belts affect general traffic safety. The objective of our study was to determine the risk factors that affect seat-belt use across the observed behaviour-related groups of adult citizens of Slovenia. Methods: Data were collected in late spring 2001, 2004, 2008 and 2012 in a cross-sectional survey, which is conceptually a part of a wider international project in the frame of the Countrywide Integrated Noncommunicable Diseases Intervention (CINDI) Programme. A stratified random sample was drawn from the Central Population Registry of the Republic of Slovenia. Results: The most significant results of our study showed that the important risk factors for seat-belt use in all three periods of examination are as follows: gender, age and education level. We have found seat-belt use in the front and the back car seats among adult citizens of Slovenia to be gradually becoming more and more prevalent. However, there are still a worrisome percentage of people who never use seat-belts. Conclusion: We will thus have to continue implementing existing activities intended to raise awareness and seat-belt use. In particular, planning stages for various public-health measures should see us focussing on at-risk population groups. Further data will have to be obtained in order for us to be able to exactly evaluate behaviour-affecting risk factors (eg psycho-physical wellbeing, use of medicinal products).