Superstars from Tiger Woods to Warren Buffett tell us the secret to their success is keeping it simple. So why would a donor-dependent, globally recognized nonprofit take a macro-economic flyer on which way currencies will move? More important: What can the disastrous Greenpeace International bet on the direction of the euro tell us about how we handle our own financial matters? Greenpeace, which is quite good at promoting peace and sustainability, is really bad at macro analysis. Sometime last year the organization lost $5.2 million—more than 6% of its annual budget—when it bet wrongly against a rising euro. This large loss came to light only this week, and it’s too soon to know its full effect. The organization says a financial pro on its staff overstepped and has been fired, and that the loss will not lead to a penny being cut from its causes. Still, it’s hard to believe that at least some donors won’t bristle and hold back donations. The consequences promise to go beyond simple embarrassment. One lesson here is that currency speculation is a tricky business and best left to hedge fund managers like George Soros. If you must engage in currency bets alone, do so with only a small fraction of your savings and through straightforward international government bond funds. These pay interest in local currency and thus represent a foreign exchange bet. You might also consider a currency ETF from leaders CurrencyShares and WisdomTree. The bigger lesson, though, is that it really does pay to keep things simple when investing. As Buffett writes in this year’s annual letter to shareholders: You don’t need to be an expert in order to achieve satisfactory investment returns. But if you aren’t, you must recognize your limitations and follow a course certain to work reasonably well. Keep things simple and don’t swing for the fences. When promised quick profits, respond with a quick “no.” Complexity is all around us. Exotic mortgages sunk millions of homeowners in the Great Recession. Unimaginably arcane financial derivatives contributed to the demise of Lehman Bros. and downfall of Bear Stearns, among other investment banks, during the financial collapse. Even bankers didn’t know quite what they were doing—not unlike the hapless, rogue finance staffer making a wrong-way bet on the euro for Greenpeace. Individuals can make things as difficult or as easy as they want when they save and invest. Annuities are especially hot right now. Many people shy away from them because they believe all of them to be complex, and many others end up in the wrong type of annuity (and many other insurance products) because so many truly are complex. Yet for most people just looking to lock up guaranteed lifetime income, the venerable immediate or deferred immediate annuity are a sound and simple option. Likewise, you can prospect for the hottest stock funds, only to be disappointed once you plunk down your dollars and see them eaten away by lackluster returns and high expenses—or you can choose low-fee diversified stock index funds, or maybe a target-date mutual fund, sleep well, and check back in just once a year to rebalance. Why layer chance on top of investment risk? You are good at something else, not macroeconomic analysis. Reports suggest that the wayward Greenpeace employee was not nest feathering but trying to do the right thing for the future of the organization. Still, it went bad—even for someone in finance. As with many endeavors, when it comes to money, better to do as Buffett says and just keep it simple.