Three metropolitan areas dominate the U.S. venture capital landscape: San Francisco, Boston and New York. These cities are home to about half of all U.S. venture firms and about half of all U.S. venture-backed companies. Though venture firms have sprung up around the country over the past 25 years, the three cities have maintained, and even expanded, their share of national firms and investment. The continuing dominance of these cities may be frustrating to policymakers, industry leaders and entrepreneurs in other parts of the country, but a recent paper argues that there is a logic behind the clustering of firms in a few cities and that this distribution may be optimal for both the venture industry and the high-tech economy.