The word out of Mexico these days is one of worry. For two straight weeks, the Bolsa, Mexico's stock exchange, has dropped, led most recently by cement giant Cemex (NYSE:CX) on concerns that construction will be down in the U.S. and Spain.

While that may turn out to be true, the Mexican economy itself looks quite robust. I just returned from a week's visit to the west coast (dodging a hurricane or two while there), and what I saw were signs that Mexico is booming.

A working vacation
I flew into tiny Puerto Vallarta airport, one of a series of airports run by Grupo Aeroportuario del Pacifico (NYSE:PAC). While I felt like I was stepping right into The Night of the Iguana (the 1960s movie was filmed here, as was the sci-fi flick Predator), the airport itself was a modern operation that was undergoing major expansion.

That wasn't the only development I saw. Hotels, condominiums, resorts, and spas were all in various stages of construction. New housing developments were rising up whole. And everything is built with cement. Both Cemex and Swiss cement leader Holcim have facilities right there in Puerto Vallarta. When Motley Fool Global Gains first recommended Cemex to subscribers, it was in part because of its diverse geographic footprint; its home country is growing at a significant pace. That would help offset any potential downturns north of the border or overseas, even as the company increased its U.S. presence with its recent purchase of Australian cement mixer Rinker.

Mexico's economy is expected to grow by 3% this year, slightly reduced from earlier 3.3% growth projections. That may seem cautionary, but the country's auto industry didn't seem to notice: Sales were up 51% year over year in July and 23% in August, following a spate of lower sales figures in preceding months.

Free trade, and lots of it
Certainly what happens in the U.S. will affect the results in Mexico. We remain Mexico's largest trading partner; since the North American Free Trade Agreement took effect in 1994, business between the two countries has expanded exponentially. Mexico realized $183 billion in exports in 2005, according to the U.S. State Department, and $118 billion in imports. That equaled 86% and 53% of the respective export and import totals. So a slowing U.S. housing market would have reverberations.

Yet Mexico also has the world's 13th-largest economy, with a gross domestic product exceeding $769 billion. Growth in production has averaged between 3% and 4.5% annually over the past three years, and inflation has been kept in check, hovering around 3.4% a year. Contrast that with when it seemed the peso was regularly devalued, and investing south of the border doesn't need to mean it'll be Montezuma's revenge on your portfolio.

The potential
U.S. companies have invested in Mexico. Intel (NASDAQ:INTC) has at least one of its design centers there, in Guadalajara. General Electric (NYSE:GE) is another that has found the Mexican economy hospitable to its needs.

Investors who take a siesta on looking there for investment opportunities risk missing out on some extraordinary profits. Mexican wireless telecom America Movil (NYSE:AMX) has returned more than 57% over the past year, while FEMSA (NYSE:FMX), which among other things runs a ubiquitous line of convenience stores known as OXXO, is up 45% in that time.

But even if you've missed out on these returns, there are still companies to invest in. Cemex is off 12% since it was first recommended in the Global Gains newsletter service at the end of May. But with domestic revenue making up 18% of its total, and sales to its home market rising 10% last quarter, it seems attractively priced -- and it has just raised guidance for the third quarter. Media company Grupo Televisa (NYSE:TV) might be another good opportunity.

Mexico is ripe for finding attractive stocks, and in the August issue, the Global Gains staff recommended another well-known name that stands to benefit from the economy's development. You can find out who it is by starting a 30-day, risk-free trial.

Opportunities to profit exist around the world, as the Fool's global investment newsletter has made clear. Yet while stocks in China, Japan, Malaysia, or Belgium may sound exotic, look close to home, too. The Bolsa may be down, but that only means it's time to start looking up Mexican companies to invest in.