An international team of accomplished researchers has been assembled to define the role that antioxidants and pro-oxidants play in cancer. Increasing scientific evidence points to the importance of antioxidants and pro-oxidants in both the aetiology of cancer development and in cancer treatments. This book should prove useful for research scientists wanting a comprehensive review of the latest accomplishment in this area and for health care-providers who advise patients and the general public about dietary antioxidants and the safety and appropriate use of antioxidant supplements. Endogenous antioxidants systems that play key roles in modulating the in vivo effects of reactive oxygen species (ROS) are reviewed in detailed. Many exogenous antioxidants such as vitamin E (tocopherols and tocotrienols), vitamin C, green tea polyphenols, beta-carotene and curcumin are individually discussed as well as their potential roles in alternative and complementary medicine approaches to cancer prevention and treatment. For public health professionals the question of whether or not antioxidants have a safe chemopreventive role is central: it is clearly much more effective to prevent cancer than deal with its consequences including the damaging side effects of many chemotherapeutics.