This chapter discusses the experience of helplessness caused increased risk for cancer, both in the short- and the long-term. It used rats because their life span is manageably short, and because a bit is known about tumor induction in this species. The chapter finds that when we increased the tumor-shock interval to four days or ten days, uncontrollable shock did not differ from controllable shock in its effect on tumor rejection. The immune system is a good candidate for such a mechanism, since Monjan and Collector found acute noise stress produced T and B cell immune suppression in mice. When these rats reached adulthood, inject them with the 50" lethal does of sarcoma and then challenged them once again with escapable shock, inescapable shock, or nothing. The chapter concludes that there is no further shock challenge as an adult, early experience with helplessness does not change the ability of the adult rat to reject tumor challenges.