For many years, investors have attempted to diversify their overall portfolios by trying to pick stocks across a diverse set of asset classes. Which is all well and good, but the problem it generally runs into is you should also be diversified within any given asset class, lest something adverse happen to the company you happened to bet on. Yet as soon as your diversifying both within, and between asset classes, now your running a portfolio of potentially 40+ equities, and even the active investor rarely has time to do due diligence on the hundreds of companies required to find 40 excellent investments.

Exchange Traded Funds are the answer. Exchange traded funds (ETFs) allow you to invest in a group of companies all at once, similar to a mutual fund. The difference is that ETFs are traded directly on a stock exchange just like a stock, they can be bought and sold any time during the day without penalty, and they are both shortable, and optionable allowing you to take advantage of both up, and down moves in the market.

The purpose of an ETF is to allow an investor to purchase a single equity that represents an investment in a sector. So if an investor is interested in buying financial stocks, they could buy XLF. If they want some small cap goodies, they can choose to buy IWM. For some exposure to the Chinese stock market, they could invest in FXI. Finally, if they simply want to emulate the returns of the S&P 500 index, the SPY has them covered.

One question remains; why should an investor choose an ETF over a mutual fund. After all, mutual funds have professional managers whose sole responsibility is the management of money. Surely these investment professionals are the best place to go for excess returns? Well there are a couple downsides to mutual funds that aren’t experienced by ETFs. First off, there are slight tax advantages for ETFs compared to mutual funds. Should a large sell of occur in a mutual fund, the mutual fund has to sell its holdings, and incur capital gains to be paid by the remaining holders of the mutual fund. Due to how ETFs are set up, this cannot occur, and so you only pay capital gains when you sell (or cover) your position.

Another advantage held by ETFs is their great convenience over their mutual counterparts. Many mutual funds have redemptions fees if you exit within 30 days, whereas ETFs aren’t plagued by this problem. Also, unlike mutual funds, you can go short an ETF, benefiting from a fall in a sector instead of a rise. ETFs can also be bought and sold any time during the trading day, using limit orders, stop losses, and all the other tools you can use for buying stock.

A great boon to ETF investors, never before experienced by mutual fund holders, is the ability to use stock options to control risk. Stock options can be used to reduce the risk by using covered calls, or buying protective puts. Alternatively, call options can be used to control maximum loss, and potentially increase profits.

When investing in ETFs, its important to consider how exactly that ETF works. This can usually be found with a quick google search. While most ETFs attain their returns simply by holding the underlying securities, other ETFs use more exotic means to match their benchmark/investment objective, sometimes with varying success. Particularly important is the differentiation between an ETF and an ETN. ETNs are debt based investments, similar to bonds in some ways, and so their value is also partially dependent on the issuer. For this reason, investments in ETNs should be approached with caution, especially in the current, credit-tight market.

ETFs are a diverse tool that allows one to remove risk from ones portfolio by investing in sectors instead of individual companies. They allow investors to benefit from downturns in markets as well as the uptrends. And they allow the investor to take advantage of options on sectors, which options-savvy investors can use to supercharge returns. Given their great variety of uses, ETFs should be a valued part of any investors portfolio, to be ignored at the investors peril.