If you wish to dampen the volatility of your foreign stock holdings, you can opt to own funds that specifically eliminate or "hedge" against currently flux.
This may not be a bad idea if you are especially risk-averse and if you are heavily invested overseas. But know that hedging will cost you.
WisdomTree Investments currently has a lineup of 14 currency-hedging ETFs, such as the WisdomTree Europe Hedged Equity ETF (HEDJ) and the WisdomTree Europe Small-Cap Hedged Equity ETF (EUSC). Both of these charge 0.58 percent a year in management fees.
Other WisdomTree offerings allow you to invest in the United Kingdom, Japan and Germany, eliminating any risk that the British Pound, Japanese Yen, or the Euro will fall in relation to the dollar, resulting in depressed returns.
But know, in addition to the cost of these funds, that you will also be lowering your take-home should these currencies rise against the dollar. If that's the case, you'll be wishing you were invested in non-hedged funds.