This factsheet describes the different mental, emotional, and behavior problems that can occur during childhood and adolescence. The incidence and symptoms of the following disorders are discussed: (1) anxiety disorders (including phobia, generalized anxiety disorder, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder); (2) major depression; (3) bipolar disorder (manic depressive illness); (4) attention-deficit/hyperactivity disorder; (5) learning disorders; (6) conduct disorder; (7) eating disorders; (8) autism spectrum disorder or autism; and (9) schizophrenia. The factsheet then describes using "systems of care" to treat children or adolescents in need of services in which local organizations work in teams with families to provide a full range of services to children and adolescents with serious emotional disturbances. Federal agencies currently studying mental, emotional, and behavior problems are also listed. (CR)