SYNOPSIS General practice prevalence figures indicate that there are between two and three women suffering from minor psychiatric illness for every man thus diagnosed. This study aims to explore possible reasons for this excess. The focus is on examining sex differences in the expression of feelings as well as symptoms, primarily in a sample of married couples selected from general practice (and characterized by a high proportion of individuals with manifest psychological difficulties) but also in a random population sample (which includes single as well as married people).The measures used include assessments of health together with indices of emotional responsiveness such as degree of satisfaction with various life domains, avowed happiness and the Affect Balance Scale, which have been developed by research workers whose interests lie mainly beyond the clinical sphere in monitoring the ' quality of life' experienced by the general population through the use of 'subjective social indicators'. These social survey techniques are here used with a more clinical orientation to give a broad focus to the question of sex differences in emotional responsiveness.The results indicate that women are, on the whole, more likely to express their feelings (both pleasant and unpleasant) than men. Men with manifest psychological problems are found to be comparatively rare and, unlike their female counterparts, "they show a drop in positive feelings of well-being rather than a rise in unpleasant feelings, as compared with the general population. Two specific groups to emerge with particularly low levels of psychological well-being are full-time housewives and older single men. It is concluded that there are underlying factors of a biological and/or social nature which predispose the sexes to show different degrees of affective response, upon which such additional influences as the frustrations of the housewife role are super-imposed.