(FORTUNE Magazine) – Uganda wanted 18 helicopters to help stamp out elephant and rhino poaching but didn't have the $25 million to pay for them. Enter Gary Pacific, head of countertrade for McDonnell Douglas Helicopter. Pacific helped set up several local projects that generate hard currency, including a plant that will catch and process Nile perch and a factory to turn pineapples and passion fruit into concentrate. Pacific says he's already found buyers in Europe. Delivery of the helicopters will start in 14 months. Such circuitous deals, long at the fringe of trade, are becoming more common as U.S. companies hungrily search for opportunity in the developing world. Dan West, chairman of the American Countertrade Association (ACA) in St. Louis and director of countertrade for Monsanto, estimates that this type of trade now accounts for 20% of U.S. exports. That's close to $110 billion of goods and services. No government figures support this estimate (there are no reporting requirements); West bases his guess on an informal survey of colleagues in his association. Most are FORTUNE 500 heavyweights, including 33 of America's top exporters (see Trade), but some are companies such as Arcon Manufacturing of Charlotte, North Carolina, which makes grain silos. What's incontrovertible is the growth of ACA: About 40% of its 176 member companies joined the six-year- old organization during the past 18 months. Says Neil Caplan, who handles such matters for Continental Grain: ''Countertrade is here to stay. It's a fact of life in certain markets.'' These include countries in Eastern Europe and the former Soviet Union that want Western goods and technology but lack the hard currency to pay for them, as well as other emerging markets. The ACA runs semiannual training seminars and offers a network of countertrade cognoscenti who are willing to share their experience and knowledge. Its new members include many who had not previously thought much about countertrade -- or even exporting. Richard Frankenheimer, who runs the trade finance division of Nynex, says his company recently joined because ''we need to be conversant in whatever techniques are in vogue so we can win bids overseas.'' Maybe you'll get an insert with your phone bill one day offering a few pounds of perch at an irresistible price.

CHART: NOT AVAILABLE CREDIT: RENEE KLEIN FOR FORTUNE/SOURCE: ACA CAPTION: TRADE TRICKS The American Countertrade Association's membership reflects the diverse companies bargaining for business in cash-poor countries.