['Dehydroepiandrosterone-sulphate (DHEAS) physiologic relevance remains controversial. However, several central nervous system and behavioural effects of DHEAS have been described. We explored the relation between DHEAS and both pituitary-adrenal axis reactivity and personality in human subjects.', 'We studied 120 consecutive patients assisted at the out patient endocrine department of a public central hospital before medical treatment. Personality was evaluated with the Minnesota Multiphasic Personality Inventory (MMPI) and the pituitary-adrenal axis reactivity was assessed with the CRH test.', 'Baseline DHEAS was inversely related to peak/basal cortisol (parcial r=-0.454, p<0.05) response to CRH infusion. DHEAS reactivity in the CRH test was directly related to the Deviant Behaviour triad (BD) (r=0.257, p<0.05) and type A personality (AP) (r=0.295, p<0.05). Basal ACTH was directly related to baseline DHEAS (r=0.366, p<0.001) and together with age and gender explained 34% of DHEAS variability.'] Is plasma dehydroepiandrosterone-sulphate related to personality and stress response?