The role of nutrition in the etiology of human disease, including cancer, has been recognized for a very long time. This knowledge and, perhaps, personal preference are reflected by the choice and balance of edibles included in the daily diet. Considerable progress has been made in identifying the cellular targets involved in interaction between cells and initiating carcinogens and promoters. It has been evident since the work of Miller and Miller (1969) that modification of cellular DNA (leading to mutagenesis) is an important event in initiating carcinogenesis. There are, of course, exceptions to the correlation between mutagenicity and carcinogenicity. Some chemicals show strong mutagenicity when tested in in vitro test systems, but they do not induce cancer in animals. Several chapters of the volume are devoted to the understanding of the mechanisms of carcinogenicity and anticarcinogenicity, as well as the role of diet or hormones in the induction or inhibition of carcinogenesis.