The Third Ministerial Conference of the World Trade Organization (WTO) was held in Seattle from November 30 to December 3, 1999. Trade ministers and other officials from the WTO's 135 member nations met in an unsuccessful attempt to plan negotiations to further deregulate free trade. Tens of thousands of activists for many causes gathered to protest what they saw as the WTO's favoring of corporate interests over social and environmental concerns.

Over 20,000 union members from the US and abroad came together for a rally and march on the opening day of the WTO conference, November 30. Here, chanting union members hold a large banner reading "March Against WTO Global Injustice." A few unions are identified by signs: the Glaziers, Architectural Metal and Glassworkers Union Local 188, the International Union of Painters and Allied Trades, District Council #5, and the Pineros Y Campesinos Unidos del Noroeste (PCUN) farmworkers union in Oregon.