The Globe and Mail reports in its Saturday edition that columnist John Heinzl's model portfolio has some U.S. exposure through the iShares Core Dividend Growth ETF (DGRO). Mr. Heinzl writes that the ETF has been the portfolio's top performer, with a price gain of about 77 per cent since the portfolio's inception on Oct. 1, 2017. One drawback of DGRO, however, is its modest weighting of about 16 per cent in information technology stocks, which have been a key engine driving the market higher. If you are looking to add U.S. exposure to your portfolio, you may want to consider a traditional S&P 500 Index ETF that will give you a tech weighting closer to 30 per cent. Another advantage is that some S&P 500 Index ETFs trade on a Canadian exchange in Canadian dollars, sparing you the expense of converting your loonies into U.S. dollars at your broker's unfavourable exchange rate. Examples include the iShares Core S&P 500 Index ETF (XUS) and the BMO S&P 500 Index ETF (ZSP), both of which charge ultralow management expense ratios of 0.09 per cent. If you are looking to control currency-related volatility, you can opt for the currency-hedged versions of these funds, which trade under the symbols XSP and ZUE, respectively.