The paper presents a summary of the study that examined the relationship between school design and adolescent identity formation. Reviewing theories and empirical studies of identity development, three major processes involved in adolescent identity formation were identified: (1) separation or individuation process, (2) social integration or relational connectedness, and (3) developmental exploration. Two key characteristics of schools that support these identity formation processes were proposed: (1) having a supportive environment addressing needs for individuation and social integration, and (2) providing opportunities for developmental exploration. Implications of these characteristics for school design were studied through a review of research and practices of learning space design. Four secondary schools in Australia which represented an innovative approach to learning space design were then examined to provide insights into these design-related implications and better understand issues and challenges associated with them. The paper concludes with proposing five design principles which supports adolescent identity development through contributing to processes involved in identity formation.