I have broad interests in near-field cosmology, stars, dark matter, and the smallest galaxies in the Universe. I do a lot of space-based observing, statistical modeling, and comparisons of data to theoretical predictions from stellar evolution and galaxy formation models. I am the PI of the JWST Early Release Science program for resolved stellar populations and PI of the HST Treasury Survey of M31 Satellite Galaxies. I am on the core leadership team of UVEX and I lead its low-mass, low-metallicity science program. The UVEX mission was selected by NASA in 2024 and is slated to launch in 2030. My research has been recognized with numerous awards including a Sloan Fellowship, a Alexander von Humboldt Fellowship, and the Newton Lacey Pierce Prize from the AAS.