The hallmarks of phobic disorders are persistent, irrational fears and avoidance of the specific things or activities (for example, air travel, closed spaces, certain animals or insects) that induce these fears. The diagnosis of a phobic disorder is made only when the phobia significantly impairs the individual's social functioning or work performance.
A common type of phobia is social phobia (also called social anxiety disorder), which affects 15 million adults (nearly 7 percent of the population). Social phobia is an undue fear of embarrassment in social situations. Although many people feel some anxiety when placed in a situation that forces them to meet and talk to new people, social phobia causes such an extreme reaction to this everyday aspect of life that it interferes with daily functioning.