Research in our group concentrates on the baker’s yeast Saccharomyces cereisiae. This model organism of modern genetics, genomics, and proteomics offers unparalleled opportunities to analyze phenotypic traits and molecular mechanisms that underlay them. Using experimental evolution we study the rate, mode and repeatability of genetic adaptation. We also ask how fitness declines when accumulation of random deleterious mutations is allowed. Our special interests are in genetic interactions whose study is critical for understanding evolution of ploidy, genetic recombination and sexual reproduction, mutational meltdown, and inheritance of polygenic traits.