Labor unions face many challenges-including changing technology, foreign competition, and declining membership. But one union occupation thrives-dockworkers. The 100,000 members of the two longshoremen unions handle nearly every item or shipping container that enters or leaves any U.S. port. With salaries averaging more than $120,000 a year, longshoremen are the highest-paid blue-collar workers in the nation, if not the world. Dock foremen average nearly $200,000 a year-more than most lawyers and physicians. At the South Carolina port of Charleston, for example, union pay is triple that of auto mechanics and truck drivers and is four times that of firefighters. The supply of applicants for dock jobs is great. When the port of Los Angeles needed 3,000 more union workers, over 300,000 applied, many of them college graduates (jobs were awarded by lottery). Why? Be sure to explain both the general situation faced by most unions, and the special circumstances of dock workers