Phenomenological features of worry such as thought content, subjective experience of worry, and efforts to control were investigated in the present interview study, as well as retrospective information about possible origins. To examine the clinical specificity of worrying in Generalized Anxiety Disorder (GAD), 36 GAD patients were compared to a normal control group (N = 30) and to a clinical control group (N = 22 social phobics). GAD patients differed from both groups in having higher frequency of worry, higher number of different worry topics, lower subjective controllability, more accompanying bodily symptoms, and more distress during worry. Thus, in general, our data confirm the central and specific role of worrying in GAD. Furthermore, in contrast to other topics, worrying about daily hassles was specific to GAD patients, which represents a lower threshold for starting to worry. Depression and Anxiety 13:89–96, 2001. © 2001 Wiley-Liss, Inc.