Past research with adult subjects has provided considerable evidence for the validity of Schwartz' (1992) theory on the structure of values. However, information about children and adolescents is scarce. The present study uses the newly developed Portraits Questionnaire (PQ-29) to test the applicability of Schwartz' values theory to this population, using a sample of 1,555 German subjects aged 10 to 17. In addition to this general research objective, the more fine-grained relation between age (used as an indicator of cognitive development) and the complexity of value structure is investigated by separately analyzing value data from different age groups. Results confirm the validity of Schwartz' theory on the structure of values in general. However, they do not show the hypothesized increase of structural complexity. Rather, value structures of 10 to 12 year olds are nearly as differentiated as those of 15 to 17 year olds.