The National Radio Astronomy Observatory (NRAO) is undertaking a major expansion of the Very Large Array (VLA), the most powerful and flexible radio instrument in the world. This VLA Expansion Project combines the existing infrastructure with state-of-the-art electronics and instrumentation to improve the scientific capabilities of the array by a factor 10 or more in all key observational parameters. Some of the most important advances include: (1) replacing the existing waveguide with optical fiber, allowing total bandwidths of up to 16 GHz, rather than the current 200 MHz; (2) installing wideband receiver systems, for continuous coverage of the entire centimeter radio spectrum from ≤1 to 50 GHz; (3) building a new correlator, able to provide as many as 262,144 frequency channels with flexible, variable resolutions between 4 MHz and 1 Hz; (4) adding ~8 new stations at distances up to 300 km from the current VLA, allowing spatial resolution as high as a few milliarcseconds on both synchrotron and thermal sources. The design and development effort for the first phase of this project has already begun, and we are currently developing a proposal for the new antennas needed for the high-resolution New Mexico Array. There are three major partners in the EVLA: NRAO; the Herzberg Institute of Astrophysics (HIA), funded by the National Research Council (NRC) of Canada; and the Mexican National Council for Science and Technology (CONACyT). We plan to finish the entire project within a decade. The EVLA will inaugurate a new era in radio astronomy, allowing extinction-free imaging of star-forming galaxies out to z>5, measurements of the three-dimensional structure of magnetic fields in objects ranging from the Sun to nearby galaxies, and parallaxes and proper motion measurements of pulsars spread throughout the Galaxy. The EVLA is intended not to perform a single, particular experiment, but to provide an essential tool across the entire range of modern astrophysics.