Abstract: While fusion has enormous potential as a source of safe, carbon-free power, the current road map seems unlikely to deliver this new energy source in time to help with efforts to mitigate global warming. However, the basis for a breakthrough is here. High-temperature superconductors have emerged from the laboratory into industrial maturity – permitting the construction of smaller, cheaper fusion devices. With the SPARC project, MIT has embarked on a project to test this premise by building a deuterium-tritium burning, mid-sized tokamak – of a size similar to many machines already in operation. Using well-known physics to project performance, we expect SPARC to produce 50-100 MW of fusion power, comfortably more than the 30 MW required to sustain it. SPARC is funded by private industry, building on the foundations of decades of fruitful, government funded research while harnessing the resources, agility and risk tolerance of the start-up culture.