Delbert M. Shankel Departments of }1icrobiology and Biochemistry The University of Kansas Lawrence, Kansas 66045 Welcome to the "International Conference on Mecha. nisms of Antimutagen- esis and Anticarcinogenesis. " We are delighted that so many of you have chosen to attend this first meeting on this important topic. The significance of genetic changes in cells has been recognized for many years. The seminal observations of Henri in 1914 (UV), Muller in 1927 (X-rays), and Auerbach in 1946 (chemical agents) established the fact that physical and chemical agents which may be present in our environment are capable of producing profound changes in heredity. It is now well-estab- lished, of course, that such changes can result in the development of can- cer, produce hereditary birth defects, alter microorganisms to cause drug resistance, or other harmful (or even beneficial) changes; it is likely that the processes of mutagenesis and the intricate balance between muta- genesis and antimutagenesis are involved in aging, evolution, and other fundamental life processe8. Consequently, we hope and believe that assem- bling thi. s group of scientists to share current fundamental and applied research in these areas will lead to a better understanding of these proc- esses and to long-term benefits for society. As stated clearly by Garfield (4), "Almost every aspect of modern liv- ing exposes us to health risks.