Among the various methods of assessing morbid anxiety the psychiatric interview remains pre-eminent. By this means, we attempt to elicit what patients actually feel—the criterion against which all other measurements are validated. Dissatisfaction with the subjective nature of psychiatric interviews and with their low reliability (Cattell and Scheier, 1958; Kreitman, Sainsbury, Morrissey, Towers, and Scrivener, 1961) has led, on the one hand, to the use of rating scales which quantify subjective clinical judgements (Kellner, Kelly and Sheffield, 1968), and, on the other, to the development of techniques which purport to measure anxiety objectively. The latter fall into two broad categories: (i) questionnaires such as the Manifest Anxiety Scale (Taylor, 1953) and the IPAT Anxiety Scale (Cattell and Scheier, 1963), and (ii) measurements of somatic correlates of anxiety, in particular the various endocrine and physiological responses reviewed by Mason (1968) and Lader (1969), respectively.