Summary: Growing demand throughout the world for wildlife and wildlife parts, ranging from rhino horns to bear gall bladders, now threatens some wildlife populations. Although the full extent of illegal trade is unknown, the value of such trade into and out of the United States is estimated at up to $250 million annually. Despite recent increases in the Fish and Wildlife Service's (FWS) wildlife inspection program, the program has had difficulty in accomplishing its mission of monitoring wildlife and intercepting wildlife trade. Given current budget constraints and downsizing within the federal government, increases in program funding are unlikely. GAO raises questions about the program's efficiency and effectiveness. The passage of the North American Free Trade Agreement is likely to increase wildlife trade among the countries that are party to the agreement--the United States, Canada, and Mexico. The expected rise in trade will increase the workload of FWS inspectors, who are already stretched thin along the U.S. borders. Wildlife inspectors, federal agency officials, and conservation and trade groups cited advantages and disadvantages to transferring FWS' wildlife inspection program to the Customs Service.