The Center for Theoretical Sciences will bring together theorists from a wide variety of fields. High energy physicists will sit down with computational neuroscientists and molecular biologists will converse with fluid dynamicists. Theorists across fields use similar tools -- e.g., nonlinear analysis, field theory, quantum mechanics, statistical mechanics, and simulations -- but have different perspectives. This combination of common tools and different perspectives will benefit not just the theorists but will likely generate new experimental research directions. Activities will include monthly seminars; common workspace with interaction days where students, postdocs, and faculty will interact with one another across fields; and long-term visitors. The Center will be a powerful recruiting tool for students, postdocs, and faculty who will appreciate the opportunity to broaden their horizons and work in an interdisciplinary environment. It will serve as the intellectual nexus of the College and a fountainhead of innovation at the university.