The goal of our laboratory's research is to understand the genetic, molecular and cellular mechanisms that control heart morphogenesis using zebrafish as a model system. Zebrafish comprise the ideal system in which to pursue this objective because 1) the transparent and externally developed embryo permits easy observation of heart development in live embryos and high-resolution in vivo imaging, 2) power embryological, genetic, pharmacological and cellular tools are available in zebrafish and 3) embryos can develop to the larval stage without functional hearts (making it possible to study the consequences of severe heart defects).