Anxiety is a basic human emotion that everyone experiences at times. Many people feel anxious, or nervous, when faced with a problem at work, before taking a test, or making an important decision. Anxiety is not typically pathological, but commonly adaptive when it facilitates avoidance of danger. Anxiety disorders, however, are different. They can cause such distress that it interferes with a person's ability to lead a normal life. For people with anxiety disorders, worry and fear are constant and overwhelming. This book examines anxiety in children and the tools and methods used to assess anxiety among young children and adolescents. It also explores the role of genetics in anxiety disorders and the connection between anxiety and temporomandibular disorder.