My main interests are Observational Cosmology and new astronomical instruments. My group (4 graduate students and one postdoc) gets most of its data from the Hubble Space Telescope (HST), the University of California's Lick Observatory (San Jose) and the Keck Observatory (Hawaii), which we operate with Caltech. These are such exciting times for astronomy, that most of us doubt that the research opportunities will ever be as good as during the next five years. The HST is producing excellent data, and Keck is 100 times faster than any other telescope in the world. It can easily make observations well beyond the reach of other telescopes, and it will have no competitors for 5 years. There is much more to do than we have time for, so we are using these advantages to tackle major questions with wide-spread implications for cosmology and galaxy formation.