With average daily turnover of $3 Trillion, the foreign exchange markets are the largest financial markets in the world.  Despite boasting such impressive volume and liquidity characteristics, forex is nonetheless considered extremely risky, and thus viewed as the bastion of experienced traders.  This is slowly beginning to change, as investors have moved to diversify their portfolios away from the traditional allocation of stocks, bonds, and cash.  Investing directly in forex still not recommended by financial advisers.  However, there exist alternative strategies, such as buying CDs denominated in foreign currencies and/or securities that are issued by foreign companies and trade on domestic exchanges.  These kinds of "indirect" strategies typically take the form of either "single play" or "double play" strategies. With both strategies, investors attempt to profit through cross-border interest rate disparities, but with "double play" trades, investors seek to profit from currency appreciation as well. The New York Times reports:

Mr. Orr advised currency buyers to research foreign nations and their credit risks, determine at the start their own risk-reward ratio and tolerance to volatility, and have exit strategies, while watching their positions constantly.

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