This study of 49 prepubertal psychiatric inpatients evaluates associations between suicidal behaviour & predexamethasone & postdexamethasone plasma cortisol levels shortly after hospital admission & 7 weeks later. Results suggest that associations between suicidal behaviour & plasma cortisol levels are independent of diagnosis. Covariation of these plasma cortisol levels with major depression was associated with severity of suicidal behaviour. Implications of these results are discussed. 34refs.