The most important predictors of early intercourse debut are reported to be poor social resources and early developing problem behaviors. In this study we have a new, additional emphasis on variables related to self-concept and social acceptance. In a population-based longitudinal study, 1399 Norwegians were followed over a 7-year span. We analyzed data using multivariate Cox-regression techniques. Early intercourse debut was part of a broader spectrum of problem behaviors, including early alcohol intoxication and early-developing conduct problems. A new finding was that a positive self-concept in the domain of ýromantic appealý was also a strong predictor, but only for boys. We suggest that the findings may have important implications for prevention and more research should be conducted along this line.