Research on worry during the past 15 years hasrevealed a remarkable amount of knowledge about thispervasive human phenomenon. Worry involves apredominance of verbal thought activity, functions as atype of cognitive avoidance, and inhibits emotionalprocessing. Worry also produces not only anxiousexperience but depressive affect as well. Recentevidence suggests that the very private experience ofworry is developmentally connected to enmeshedchildhood relationships with the primary caregiver andis currently associated with significant interpersonalproblems, especially those involving tendency to be overly nurturing to others. At thephysiological level, worry is characterized peripherallyby parasympathetic deficiency and autonomic rigidity andcentrally by left-frontal activation.