Our research group designs experiments and develops analytical methods to study the properties of the Universe through measurements of the Cosmic Microwave Background radiation (the CMB) and other extra-Galactic observables. The prediction, and subsequent observational confirmation, of this relic background represents one of the most important pillars of modern observational cosmology and continues to yield insights regarding the early Universe, the nature of dark matter and dark energy, and other areas of fundamental physics. Comparison of the statistical properties of the CMB with the predictions of parametric models has revolutionized our understanding of the basic physics that governs the large-scale properties of our Universe. New measurements of the gravitational lensing of galaxy clusters have the potential to characterize the nature of dark matter. Through novel instrumentation and techniques, we use the Universe as our laboratory for fundamental physics.