Anxiety may be experienced in a variety of response modes. There is evidence to suggest that panic disordered individuals differ from individuals with other anxiety diagnoses in that they experience a greater increase in somatic symptoms and catastrophic cognitions. Further it has been suggested that panic disordered individuals, as compared to other anxiety disordered individuals, experience greater global anxiety and depression. The present study compared the total scores of 93 disordered subjects on the Symptom Assessment Questionnaire and the Cognitions Assessment Questionnaire and found that both questionnaires discriminated panic disordered subjects from non-panic disordered subjects. The two questionnaires also discriminated subjects with panic attacks from subjects without panic attacks. Item analyses were conducted on both questionnaires in order to identify specific items which differentiated panic disordered subjects from non-panic disordered subjects and subjects with panic attacks from subjects without panic attacks. Factor analyses were conducted on both questionnaires, resulting in the identification of somatic and cognitive factors salient to the phenomenon of panic. In general, the identified factors supported and expanded upon the panic symptoms listed in DSM-III. Finally, two widely used measures of anxiety and depression were administered to subjects. Panickers scored higher than Non-panickers on measures of state-anxiety, trait-anxiety, and depression. The Panic Disordered Group scored higher than the Non-Panic Disordered Group on the depression scale. However, the Panic Disordered Group scored no differently from the NonPanic Disordered on the state-anxiety and trait-anxiety inventories, suggesting that the presence of panic attacks in all anxiety diagnostic groups weakened the ability of the tradition anxiety measures to distinguish between the comparison groups. / M.S.