As the North American Free Trade Agreement struggles to get under way (and Ross Perot, we hope, stays out of the way), here's how several growing companies are responding:

For computer-mapping company Applied Geographics, there's a payoff already. CEO Joan Gardner, who was waiting for the word on a $500,000 project to map parts of Mexico City's water-and-sewer system, got it "the day after NAFTA passed." The contract puts the young Boston business at nearly $2 million in sales.

The trade agreement should end the days of U.S. salespeople's being detained at Canadian customs. "Now we should be able to promise better service to Canadian customers," says Brian Brockway, CEO of Data Sciences, in St. Paul, Minn., which last year got about 55% of its $3.9 million in sales from exports.

"It will allow us to get very quickly into manufacturing that we couldn't do in the United States," says Chris Nowak, CEO of Rocky Mountain Motorworks, a $5-million mail-order distributor of Volkswagen car parts in Woodland Park, Colo. He is scouting out plants in Mexico, where the Bug is, incidentally, the number-one-selling car.

Tom Reisinger, president of $21.4-million Hub City Indianapolis Terminals, a shipping service based in Indianapolis, speculates that with tariffs off in Mexico, his U.S. customers in the hard-hit aluminum industry will be able to even the score against the Russians, who've slashed prices mercilessly. As a result, Hub City expects to move more aluminum into Mexico.

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