Conventional portfolio wisdom holds that adequate portfolio diversification is impossible unless one holds many securities, and that a diversified portfolio overall is less risky than a concentrated one. The question of how many securities one should hold in a portfolio to achieve adequate diversification is considered with the conclusion that concentrating a portfolio on a few choice assets dramatically increases an investor’s chance of superior performance. Investors who avoid concentrated equity miss out on the triple benefits of excess returns, lower risk, and lower correlations.