Implicit motives represent nonconsciously represented dispositions to seek specific classes of incentives and to avoid corresponding classes of disincentives. Growing evidence suggests that the implicit power motive is associated with basal levels and reactivity of the gonadal steroid hormones testosterone in men and estradiol in women. It is also associated with increased release of stress hormones (cortisol, norepinephrine) in response to dominance challenges and social defeat. The implicit affiliation motive is linked to the release of progesterone: increases in progesterone are followed by increases in affiliation motivation, and arousal of affiliation motivation is associated with concurrent or subsequent progesterone increases. There is limited evidence for a role of vasopressin in achievement motivation. These findings point to a key role of the hypothalamus for implicit motives, a role that is consistent with the existence of function-specific nuclei within this brain area.