Young people can have mental, emotional, and behavioral problems that are real, painful, and costly. These problems, often called "disorders," are sources of stress for children and their families, schools, and communities.
The number of young people and their families who are affected by mental, emotional, and behavioral disorders is significant. It is estimated that as many as one in five children and adolescents may have a mental health disorder that can be identified and require treatment.

Mental health disorders in children and adolescents are caused by biology, environment, or a combination of the two. Examples of biological factors are genetics, chemical imbalances in the body, and damage to the central nervous system, such as a head injury. Many environmental factors also can affect mental health, including exposure to violence, extreme stress, and the loss of an important person.

Families and communities, working together, can help children and adolescents with mental disorders. A broad range of services is often necessary to meet the needs of these young people and their families.
The Disorders

Below are descriptions of particular mental, emotional, and behavioral disorders that may occur during childhood and adolescence. All can have a serious impact on a child's overall health. Some disorders are more common than others, and conditions range from mild to severe. Often, a child has more than one disorder (U.S. Department of Health and Human Services, 1999).
Anxiety Disorders

Young people who experience excessive fear, worry, or uneasiness may have an anxiety disorder. Anxiety disorders are among the most common of childhood disorders. According to one study of 9- to 17-year-olds, as many as 13 of every 100 young people have an anxiety disorder (U.S. Department of Health and Human Services, 1999). Anxiety disorders include:
Phobias, which are unrealistic and overwhelming fears of objects or situations.
Generalized anxiety disorder, which causes children to demonstrate a pattern of excessive, unrealistic worry that cannot be attributed to any recent experience.
Panic disorder, which causes terrifying "panic attacks" that include physical symptoms, such as a rapid heartbeat and dizziness.
Obsessive-compulsive disorder, which causes children to become "trapped" in a pattern of repeated thoughts and behaviors, such as counting or hand washing.
Post-traumatic stress disorder, which causes a pattern of flashbacks and other symptoms and occurs in children who have experienced a psychologically distressing event, such as abuse, being a victim or witness of violence, or exposure to other types of trauma such as wars or natural disasters.