Just a few years ago, the American economy was in dire financial straits. Money was tight and people cut way back on discretionary spending. The casino companies in Las Vegas took quite a hit as a result of this slowdown.

But today, the world is a different place, especially for gambling companies -- thanks to Asia.

A new gambling mecca
Fortunately, casino companies had already begun moving eastward to China's only legal gambling destination -- Macau. The rest, as they say, is history. If you want to quantify the great Macau success story, consider this: Macau generated $33.5 billion in annual gambling revenue last year -- five times that of the Las Vegas Strip.

Does the growth story end here? Of course not.

Beyond borders
Sheldon Adelson, chairman and CEO of Las Vegas Sands (NYSE: LVS), has been showing a lot of interest in expanding his casino operations to continents beyond the U.S. and Asia. The casino magnate has been in the news recently for his "Euro-Vegas" proposition, as he plans to invest a massive amount into building a casino in Spain. This offer is not just potentially lucrative for Adelson, but seems tempting for the Spanish government, as the country's economy is estimated to shrink by 1.7% this year.

Asian appetite
While Adelson's Spanish plans are yet to be finalized, there is a lot of buzz about more casino destinations being planted in Asia itself. Unlike the Spanish investment, which is primarily Sands' initiative, casino development in various Asian locations, such as the Philippines, Vietnam, Korea, and Japan, is something other casino biggies such as Wynn Resorts (Nasdaq: WYNN) and MGM Resorts (NYSE: MGM) want to pursue.

Of these locations, the Philippines seems to have grabbed quite a lot of investor attention lately. Although gambling has been legal there for quite some time, the destination remained unpopular because of its high crime rate and poverty. U.S.-based casino companies can attempt to change this image.

But these U.S. operators already face competition from local players such as Malaysia-based Genting, Hong Kong-based Melco Crown Entertainment (Nasdaq: MPEL), and Galaxy Entertainment, all of which are looking to develop luxury tourist and gambling destinations in this location.

In fact, according to brokerage firm CLSA, if only three resorts are built in the Philippines, its gambling revenue could grow to as much as $3 billion by 2015, from $1.3 billion in 2011.

Local players = stiff competition
Entry into this market by foreign companies will certainly not be an easy task, as Asian gambling companies are actively building and expanding their respective casino empires. Firstly, Enrique Razon Jr., owner of Bloomberry Resorts, plans to spend $1.2 billion to build a luxury casino resort in Manila, which would contain 300 gambling tables and VIP villas, among other facilities.

Secondly, Genting has been showing an interest in Vietnam and in the Philippines as possible destinations. With a hefty cash reserve of nearly $3.1 billion and recently raised debt amounting to $1.8 billion, Genting looks well-armed to expand into the area.

Among other players already operating in this area are Belle and Universal Entertainment. The latter is owned by Japanese magnate Kazuo Okada, who is expanding in the Philippines and South Korea. And that's not all, as other local players such as Galaxy Entertainment and Melco Crown are desperately trying to break into these markets.

On the other hand, there is another new kid on the Nasdaq who's probably looking at good old China from a different angle. Caesars Entertainment (Nasdaq: CZR) hasn't built any property in Macau and has no plans to do so. But the company has a unique plan for entering Asia, by building a nongambling luxury resort in Hainan, a tourist destination in South China.

The Foolish aftermath
A robust expansion by local players is likely to take the sheen off some of the prospects connected to this region for global players. However, when it comes to big investments, global players clearly have the upper hand. Whether or not these smaller players can win in their more local markets remains to be seen, but either way it's a trend investors need to watch.

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