International stocks have strongly underperformed U.S. stocks this year. Such a large gap may lead many to questioning the value of owning stocks outside the U.S. As part of our investment approach, we see the inclusion of international equities as a natural extension of the diversification we pursue in all our portfolio exposures. Indeed, we see diversification across a range of historical periods as having allowed stronger performance among particular segments of the equity universe to offset weaker returns from others. The range of differences in performance and shifts in ranks among the segments over time may surprise some readers. That surprise is chief among the rationale for our pursuit of diversity.