This Institute reviews the complexities of adolescence primarily from the perspective of social cognition, with a view to the developmentally appropriate applications of mentalization focused-based treatments modalities for an adolescent target population. Recent discoveries in both neuroscience and developmental research focus our attention on adolescence as a critical period for the establishment of long-term patterns of adaptation in many ways analogous to the first four years of life. Adolescence represents a key period of brain development both in terms of structural and functional changes which are associated with changes in emotional reactivity as well as social cognition. These recent discoveries have profound implications for our clinical approach to this age group which epidemiologically represent the most profound challenges not only to child psychiatry but also to adult psychiatric colleagues. Perhaps up to 75% of psychiatric problems apparent between the ages of 18 and 26 are present already under 18 years of age, the vast majority emerging during adolescence.The first presentation reviews the work on social cognition that suggests adolescence is a special period of heightened emotional reactivity and relatively limited capacity for considering the implications of decision-making, particularly in social contexts. A parallel may be drawn between the characteristics of 'normal' adolescence and those of adults with a diagnosis of borderline personality disorder. This may offer helpful insights in understanding mental disorders characteristic of adolescence such as eating disorders, self-harm and other impulse problems. Dr. Geid's subsequent presentation grounds the first one. It reviews recent neuro-scientific work emerging in relation to adolescence, specifically, key structural and functional changes revealed by MRI and fMRI investigations. Specifically, Dr. Geid discusses imaging studies that document the neuro-circuitry involved in adolescent decision making and social cognition, particularly the weighting of limbic and pre-frontal cortex. Building on these neuro-scientific and psychological models of this developmental phase, presenters describe three clinical applications. First, Dr. Target discusses a multimodal treatment model for adolescents with severe psychological problems normally requiring hospitalization, but managed in the home where the organizing theme of the intervention is attachment and social cognition. Next, Dr. Sargent discusses necessary modifications of structural family therapy to take into account deficits of adolescent social cognition using clinically based examples. Finally, presenters describe an alternative therapy approach using short-term mentalization and relational therapy with adolescents and illustrate with video examples. A panel discussion with audience participation is included at the end of the day.