This qualitative study of travel-related risk behaviours of Slovene injection drug users was based on interviews with individuals enrolled in drug addiction treatment programmes run by three regional centres for prevention and treatment of drug addiction. The primary objective of the study was to analyse behaviour patterns and practices of injection drug users during travel. Methods:Travel-related problems of Slovene injection drug users were identified on the basis of data obtained by 25 in-depth interviews. A semi-structured questionnaire with 13 open-ended questions was developed after a preliminary study and review of the literature, and on the basis of experience with the treatment of drug addiction in Slovenia. Results: The sample comprised 25 individuals, 18 men and seven women, aged 25 to 53 years. The interviews were 10 to 30 minutes long. The results obtained were presented as identified risk behaviours. Five categories were generated, providing information on the following topics: procurement of illicit drugs, criminal acts/environment, HIV and hepatitis B and C infections, storage and transport of substitution medication and pre-travel health protection. The first three categories comprise the injection drug users’ risk behaviours that are most frequently explored in the literature. The other two categories – storage and transport of medication across the border and pre-travel health protection – reflect national specificities and the effectiveness of substitution treatment programmes. The majority of participants denied having shared needles and other injecting equipment when travelling. Participants who had no doctor’s certificate had recourse to various forms of risk behaviour, finding a number of ways to hide the medication at the border. Conclusion: This qualitative study provides insight into potential travel-related risk behaviour of injection drug users from two Slovene regions – central and coastal. The potential value of this qualitative study is primarily in the identification of potential risk behaviour of Slovene injection drug users travelling abroad. The study shows that injection drug users’ experiences can contribute to better and more efficient treatment of drug addiction in Slovenia.