Main Scientific Contributions: The standard model for supernova feedback and the formation of dwarf galaxies (2000 citations). Understanding the structure and evolution of dark-matter halos (2500). Analyzing the cosmic velocity field for determining the density of dark matter and dark energy (2100). Dynamics of large-scale structure and the relation between galaxies and the underlying dark matter (1200). Understanding basic processes in galaxies, and in particular the central role of cold streams in galaxy formation, including the galaxy bimodality, the intense star-forming galaxies at high redshift, and the quenching of star formation in ellipticals (2500 citations to ongoing work).