[영문]Aims: This study explores the perception of sexual risk-taking behaviour in young HIV+ women and men in Sweden and their understanding of why they caught HIV. Method: In-depth interviews were conducted with 10 HIV+ women and men aged 17-24 years, 7 born in Sweden and 3 immigrants. Interviews were tape-recorded, transcribed verbatim, and analysed according to the stages of grounded theory. Results: The core category varying agency in the gendered sexual arena illustrated a spectrum of power available to these informants during sexual encounters. Two subcategories contextualized sexual practice: sociocultural blinds and from consensual to forced sex. Lack of adult supervision as a child, naive views, being in love, alcohol and drugs, the macho ideal, and cultures of silence surrounding sexuality both individually and structurally all blinded them to the risks, making them vulnerable. Grouping narratives according to degree of consensus in sexual encounters demonstrated that sexual risks happened in a context of gendered power relations. Conclusion: This pioneering study reveals mechanisms that contribute to vulnerability and varied agency that may help in understanding why and how young people are at risk of contracting HIV. Public health strategies, which consider the role of gender and social background in the context of risky behaviours, could be developed from these findings.