The focus of this study is on identifying how Interpersonal Psychotherapy for Adolescents (IPT-A) with depression works to change sleep and related biological markers found in saliva, namely cortisol and pro-inflammatory cytokine levels. The long-term goal of this project is to understand the biological mechanisms of recovery from depression in order to assist in selecting and guiding personalized psychotherapeutic interventions with the highest likelihood of success for individual adolescents with depression.

The primary aim of this project is to examine whether adolescent depression and the associated symptoms of sleep disturbance are best treated using an empirically supported psychotherapy that is augmented with a sleep improvement module. Twenty adolescents (ages 12-17) who meet criteria for major depressive disorder, dysthymic disorder, depressive disorder not otherwise specified, or adjustment disorder with depressed mood and also report elevated levels of sleep disturbance will receive Interpersonal Psychotherapy for Depressed Adolescents (IPT-A) with an adjunctive sleep module that is integrated throughout the treatment. Identifying the best approach to treating both the adolescent's depression and the commonly associated symptom of sleep disturbance will have significant implications for the long-term outcomes of depressed adolescents. Moreover, identifying unique symptom and biological profiles at the outset of treatment may enable doctors to predict treatment outcome.

Inclusion Criteria:

• outpatient participant
• parent or legally authorized representative must provide consent and assent by the participant
• Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-V) criteria for a depressive disorder
• Clinical Global Assessment Scale (C-GAS) < 65
• Quick Inventory of Depression Symptoms - Self Report 16 (QIDS-SR16) over 8 and less than 24.
• English speaking
• significant sleep complaints

Exclusion Criteria:

• co-morbid psychiatric diagnosis of bipolar disorder, psychosis, autism spectrum disorder, intellectual development disorder, conduct disorder or substance abuse disorder
• any condition or illness such as uncontrolled seizure disorder, uncontrolled diabetes, or any other conditions that represent as an inappropriate risk to the participant and/or could confound the interpretation of the study
• currently in active evidence-based psychotherapy for the same condition
• currently taking medication for a psychiatric diagnosis that is not a stable dose (4 weeks on the same dose).
• currently considered at risk for suicide in the opinion of the study doctor, has made a suicide attempt in the past 4 months, or is currently reporting active suicidal ideation.
• history of alcohol or other substance abuse as defined by DSM-V within the last 6 months.
• evidence from clinical diagnosis or report by youth or parent of sleep apnea, restless legs or periodic limb movements during sleep
• sleep treatment that might confound the interpretation of sleep outcomes.