Adolescence is key period for reward circuit development and the emergence of depression. The Impact of Puberty on Affect and Neural Development across Adolescence (iPANDA) project is an ongoing longitudinal multi-method (ERPs and fMRI) study of within-subject trajectories of reward sensitivity and depressive symptoms in a large sample of adolescent girls. The iPANDA project includes a baseline assessment (T1: ages 8 to 14) and three follow-up assessments (T2: ages 10 to 16; T3: ages 12 to 18; and T4: ages 14 to 20) of neural reward sensitivity and psychopathology. The study aims to examine in adolescent girls whether baseline indicators of risk for depression predict developmental trajectories of reward sensitivity, developmental trajectories of reward sensitivity predict depression, and the impact of stress on developmental trajectories of reward sensitivity and depression.