The transition from childhood to adolescence is a period which bears with it risks for both psychological and physical health problems, such as problems with forming one’s identity and problems related to sexuality (Transitions Theory, Meleis). There are gaps in knowledge about young people’s conceptions and experiences which have a decisive significance for the design of interventions for health promotion and disease prevention. The aim of the research project is to investigate young people’s sexual behavior along with their conceptions of “the love ideal”, sexuality, and sex and relationship education. The project is divided into three studies and utilizes quantitative as well as qualitative data. Study 1: High School Students’ sexual behavior and self-esteem, data collection done by a survey (the study has been published). Study 2: Adolescents’ conceptions of learning about sex and relationships, condom, use along with testing for Chlamydia. The design of the study is qualitative with focus group interviews, analyzed on the basis of phenomenography. The study will result in two articles, or which the first article soon to be submitted. Study 3: Adolescents’ conceptions of “the love ideal” and the art of communication about needs. The study was carried out through individual in depth interviews (data collection completed) and analyzed by a phenomenographic method. The results are expected to contribute with knowledge about adolescents’ conceptions of sexuality and sexual behavior in order to optimize health promotion measures in youth clinics as well as in school health service.