The Louis group is interesting in exploring and exploiting the genetic and phenotypic diversity of Saccharomyces yeasts. Earlier work on the yeast genome, particularly the diverse subtelomeric regions, led to studies of related species and diversity within species. A landmark population genomics survey and 2009 led to the development of new approaches to quantitative trait analysis in S. cerevisiae where multigenerational advanced inter-cross lines and next generation sequencing of individuals and selected pools of individuals provides high resolution, high sensitivity detection of causal genetic variation underlying various traits. Most recently we have cracked the sterility of yeast hybrids and can apply the same quantitative genetics to these important workhorses of fermentation. We are developing improved strains through breeding and determining the genetic architecture of those improvements.