Unlike past letters, this commentary is focused on a singular topic; the role of diversification in a portfolio. We chose this topic because for most of the past 10 years, US investors have not benefited from portfolio diversification. At least it feels that way, given that no public asset class has come close to matching the performance of US stocks. Who wants to own overseas stocks when US equities have compounded at double the rate? Who wants to own bonds when yields are relatively low, and US stocks have appreciated with relatively little volatility? Download Q3 2018 commentary.