Sansone, Weir, Harpster, and Morgan (1992) found that individuals intentionally regulated their interest in an activity when they had both the need (the task was boring) and a reason to exert the effort (an ostensible health benefit). The present study examined Hardiness and Conscientiousness as moderators of this self-regulatory process when individuals had the option of quitting in addition to the options of persisting and of engaging in interest-enhancing strategies. Undergraduates performed a boring copying activity under instructions to stop when they felt they could evaluate the task. Half were told that their evaluations would help researchers develop good jobs for others (Benefit). Results indicated high hardy individuals copied more letters when they were provided the additional Benefit information, and this effect was mediated through their attempt to make the task more interesting. High conscientious individuals persisted longer than individuals lower in conscientiousness independently of the benefit manipulation or strategy use. Implications of individual differences in self-regulation of motivation are discussed.