This book represents an attempt at psychological research on contemporary Bulgarian adolescents through the prism of three fundamental characteristics: 1) the status of their psychosocial and national identity; 2) their value system; 3) their mental well-being. A new approach to the study of national identity from the perspective of its development is proposed. The hypothesis of the existence of four statuses of national identity, which characterize it as a dynamic construct, is substantiated. The results of two large empirical studies of Bulgarian adolescents, covering more than 1,000 people from different cities in the country, are presented and interpreted. The results are summarized with the help of a portrait description of four groups of Bulgarian adolescents—in moratorium, diffusion, with established and predetermined psychosocial and national identity. The possibilities for applying the results in pedagogical and psychological counseling practice are also discussed. The book may be of interest to both the scientific community and a wide range of readers interested in the problems of adolescent development.