A common complication of panic disorder is agoraphobia, anxiety about being in a place or situation where escape is difficult or embarrassing (Craske, 2000; Gorman, 2000). It seems that the definition of the word has expanded to refer to avoidance behaviors that sufferers often develop. If a sufferer of panic attacks seems to have them while driving, for example, then he or she may avoid driving, which relieves the anxiety, and subsequently makes future driving more difficult, as a result of behavioral reinforcement.