American blue chips have been the backbone of many investors' portfolios for the past century. In fact, Coca-Cola, Merck (NYSE:MRK), and Tootsie Roll (NYSE:TR) were three of the best S&P 500 stocks from 1957 to 2003, according to research by Wharton professor Jeremy Siegel. For some, these stocks helped build sizable fortunes.

Though some domestic large caps like Weyerhaeuser (NYSE:WY) have slashed their dividends this year, those with strong balance sheets and plenty of free cash flow to support their payouts will continue to play an important role in our portfolios into the 21st century.

But restricting yourself to just American blue chips now would be like entering a prizefight with one hand tied behind your back. To capitalize on the benefits of this century's best dividend-paying stocks, you need to look outside our borders.

Stamp your passport
Over the past decade -- especially the past six years or so -- it has become clear that the global economy has become more closely integrated than at any other point in history. Today, capital can find its way to just about any country with relative ease, allowing investors to search the globe for the best available returns.

What's more, you're likely to find more companies paying higher dividends abroad. The average dividend yield of the U.K.'s FTSE 100, for example, is 3.3% -- a good bit higher than the S&P 500's 1.8%. Moreover, the NZX 50 index in New Zealand pays more than twice as much as the S&P, with an average dividend yield of about 4.5%.

It isn't even close
Foreign cash cows have been beating up their American counterparts since 2003, even including recent market volatility. A screen on Capital IQ for companies capitalized at greater than $1 billion, with a current dividend yield exceeding 2%, illustrates the profound disparity quite nicely.

Despite the global market downturn, which in many countries has been far worse than in the U.S., about 39% (51 of 130) of foreign dividend-paying stocks that trade on a U.S. exchange have more than doubled in the past six years. Included in this group are Alcon (NYSE:ACL) and CNOOC (NYSE:CEO).

On the other hand, only 17% (59 of 339) of U.S. companies that meet these criteria have more than doubled since November 2003. Some of the select stocks on this list include McDonald's (NYSE:MCD) and Chevron (NYSE:CVX).

Achtung, baby
There are always added risks to consider (politics, currency, etc.) before investing abroad, but dividend-minded investors stateside will want to note two things in particular:

1. Dividend regularity. Or lack thereof. Foreign-company dividends may be larger, but they're often less regular in timing and amount. Companies abroad like to pay out a target percentage of earnings instead of a certain dollar value every year. Don't knock it: Freed from the pressure to lowball their payouts, these companies can pay you more over the long haul.

2. Dividend taxation. Foreign countries (the U.K. is an exception) will scalp your scratch by their going rate. Still, most countries in which you're likely to invest have tax treaties with the United States (search for "IRS publication 901" using Google for the complete list), meaning you can claim a credit for the tax withheld. Here's the rub: Because a credit offsets taxes you would have otherwise paid, it's smart to hold foreign stocks in a taxable account. In other words, skip the IRA if you're going abroad.

Feeling overwhelmed, but don't want to pass up the double benefit of foreign growth potential and dividends? I urge you to consider a free examination of the Motley Fool Income Investor service, and to join us in our quest to find the world's best dividend payers.

The Income Investor service has more than 20 active international recommendations at present, plus a stable of domestic dividend divas. Moreover, 84% of their picks continue to outperform the S&P 500 while posting an average dividend yield of 4.2%. You can get your free guest pass through this link.

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This article was first published June 28, 2007. It has been updated.

Fool analyst Todd Wenning is split on whether Achtung Baby or The Joshua Tree is the best U2 album. He owns no shares of any company mentioned. Coca-Cola is a Motley Fool Inside Value and an Income Investor selection. CNOOC is a Global Gains selection, and Alcon is a former one. The Fool's disclosure policy pays dividends on the daily.