Given the multitude of asset classes and countries available for investment, no one has been able to prove that they can consistently predict which will be the top, or bottom, performer. Absent this skill, diversification has proven time and again to be the best long-term strategy. There will never be years where diversification outperforms every asset class, but there will be no years where diversification underperforms every asset class. Layer on strategic rebalancing and a diversified allocation should outperform the majority of individual asset classes in the long run. A Wealth of Common Sense looks at the historical application of this in their article on Global Diversification.