Positive youth development (PYD) focuses on positive qualities of youth and how such qualities can promote thriving as well as healthy development. PYD research on the association between developmental assets and thriving shows that young people who report numerous developmental assets also report many thriving indicators. However, to date little research has been performed in this field in Norway. Our study thus extends PYD research by investigating the associations between developmental assets and thriving among 591 Norwegian high-school students (55% girls). The participants' average age was 16.70 years (SD = .90). Findings from correlation analysis indicated that all eight developmental assets being examined correlated significantly with thriving, which was assessed as a composite variable reflecting good physical health, leadership, delayed gratification, overcoming of adversity, valuing of diversity, school success, and helping others. Still, regression analysis showed that only two of four internal assets (i.e., commitment to learning and positive values) and two of four external assets (i.e., empowerment and constructive use of time) remained significantly associated with thriving. The regression analysis also showed that developmental assets, along with the demographic variables: age, gender, and parents' educational level, accounted for 21% of the variance in thriving, while developmental assets alone accounted for some 19% of the variance. The findings suggest that developmental assets can provide a good