Exchange-traded funds offer a convenient way to invest in sectors or niches that interest you. If you'd like to add dividends and international stocks to your portfolio, the WisdomTree DEFA ETF (NYSE: DWM) could save you a lot of trouble. Instead of trying to figure out which companies will perform best, you can use this ETF to invest in a lot of them simultaneously. It focuses on dividend-paying companies based in Europe, Far East Asia, and Australasia, and its dividend yield was recently 4.3%.

The basics
ETFs often sport lower expense ratios than their mutual fund cousins. The WisdomTree ETF's expense ratio -- its annual fee -- is a relatively low 0.48%.

This ETF has roughly kept pace with its benchmark over the past three and five years. As with most investments, of course, we can't expect outstanding performances in every quarter or year. Investors with conviction need to wait for their holdings to deliver.

With a turnover rate of 30%, this fund isn't frantically and frequently rejiggering its holdings, as many funds do.

What's in it?
Plenty of large, global, dividend payers performed well over the past year. GlaxoSmithKline (NYSE: GSK), for example, based in the U.K. and recently yielding 4.8%, gained 10% over the past year. Detractors don't like its relatively slow growth and its steep debt load, but bulls enjoy its growing dividend and are optimistic about the company's restructuring plan as it invests more heavily in developing new treatments.

U.K.-based telecom giant Vodafone (Nasdaq: VOD), recently yielding 3.4%, advanced 9%. It's seen by many as a great play on the growing global middle class. Vodafone has announced plans to buy Cable and Wireless Worldwide, and holds a 45% stake in Verizon Wireless. Its stock has been held back some due to concerns over Europe's economic woes, though.

Other companies didn't do as well last year, but could see their fortunes change in the coming years. Spanish telecom giant Telefonica (NYSE: TEF) sank 37%, with Europe's big fiscal troubles not helping it. It recently yielded 7.6% even after a dividend cut, and on the plus side, its Latin American operations and even some of its European business has been growing well.

France Telecom (NYSE: FTE) shed 33%. The company recently yielded more than 13%, but it's planning to cut its dividend this year as it tries to conserve cash. Some don't like that the French government owns a big chunk of the company, and are wary of its exposure to shaky Europe, but it's also been pleasing some with its shift in focus from landlines to digital delivery. Its Latin American operations have also been posting solid growth. My colleague Sean Williams thinks both Telefonica and France Telecom look attractive at recent levels.

The big picture
A well-chosen ETF can grant you instant diversification across any industry or group of companies -- and make investing in and profiting from it that much easier.

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