There is increasing evidence that women at the outset of sexual activity do not need to have sexual desire, as in 'drive', and that many do not distinguish desire from arousal. Multiple modes of investigation confirm poor correlation between women's subjective arousal and measured genital congestion. Suggested revisions to the DSM-IV definitions of sexual disorder have been published: there is now need to align interview assessments and screening questionnaires with contemporary understanding of women's sexual response. Whereas the psychological factors associated with women's sexual function and resilience to biological insults and external stressors are well documented, the role of biological factors is less clear. Variations in the rate of decline of adrenal and ovarian pro-hormones, activity of converting enzymes in peripheral cells, sensitivity of androgen and estrogen receptors and cerebral production of sex steroids may all be involved. Thus there is great complexity underlying the question of sex hormone supplementation, and in particular, little clarity as to which women have decreased brain and/or peripheral androgen activity. When psychosexual etiological factors appear to be minimal and investigational testosterone supplementation is considered, it would be appropriate to target women with disordered arousal and desire in keeping with the recently recommended revised definitions.