ABSTRACTClinical, psychophysiological, and psychometric measurements were made on 20 normal controls and 30 anxious patients during rest and experimental stress. Resting forearm blood flow, a relatively new physiological index of anxiety, was found to correlate significantly with clinical and subjective ratings of anxiety, and with heart rate, number of spontaneous fluctuations of skin resistance, and amplitude of forearm EMG. It did not correlate significantly with any of the measures of depression. Resting forearm blood flow and heart rate were found to be better measures of arousal in this study than skin resistance, EMG, or cutaneous vasomotor status, since the latter did not show significant differences between anxious patients and normal controls. The psychological traits of the two groups were also assessed by the Maudsley Personality Inventory, Taylor Manifest Anxiety Scale, and Zung Depression Scale; and their emotional state evaluated by the Clyde Mood Scale and Semantic Differential Scale. Twenty‐one variables showed significant differences between the two groups. Some of these measures have subsequently been used, with advantage, to monitor emotional changes brought about by psychiatric treatmen