The study examined the relationship between the Type A behavior pattern and personality hardiness and predicted an interaction between the two that would be influential for illness onset. Type A and hardiness were found to be conceptually different and empirically independent factors. Under high stressful life events, male executives who were high in Type A and low in hardiness tended toward higher general illness scores than any other executives. Type A and hardiness emerge from this study as bases for extrinsic and intrinsic motivation, respectively.