Book excerpt: Diversification provides a well-known way of getting something close to a free lunch: by spreading money across different kinds of investments, investors can earn the same return with lower risk (or a much higher return for the same amount of risk). This strategy, introduced nearly fifty years ago, led to such strategies as index funds. What if we were all missing out on another free lunch that’s right under our noses? InLifecycle Investing, Barry Nalebuff and Ian Ayres-two of the most innovative thinkers in business, law, and economics-have developed tools that will allow nearly any investor to diversify their portfolios over time. By using leveraging when young-a controversial idea that sparked hate mail when the authors first floated it in the pages ofForbes-investors of all stripes, from those just starting to plan to those getting ready to retire, can substantially reduce overall risk while improving their returns. InLifecycle Investing, readers will learn How to figure out the level of exposure and leverage that’s right foryou How the Lifecycle Investing strategy would have performed in the historical market Why it will work even if everyone does it Whennotto adopt the Lifecycle Investing strategy Clearly written and backed by rigorous research,Lifecycle Investingpresents a simple but radical idea that will shake up how we think about retirement investing even as it provides a healthier nest egg in a nicely feathered nest.