Following intense advocacy by Human Rights Watch, Democratic leaders from the House of Representatives announced on June 29 that they would oppose a US-Colombia Free Trade Agreement (FTA) until Colombia shows evidence of sustained results in addressing violence against trade unionists and paramilitary abuses. This decision imposes real pressure on Colombia to combat these crimes. Human Rights Watch has long urged the United States, Colombia’s largest donor, to tie assistance to human rights benchmarks. On June 28, we testified at a congressional hearing about violence against trade unionists, the impunity enjoyed by the majority of the perpetrators (most of whom are paramilitaries), the largely failed paramilitary demobilization process, and the responsibility of multinational corporations in Colombia toward trade unionists. We met with the Office of the US Trade Representative to recommend that meaningful human rights pre-conditions be included in the agreement, and with members of the House Ways and Means Committee and other members of Congress to urge them to oppose the agreement until Colombia reins in the paramilitary units that have been killing trade unionists and many others. Through media interviews, op-eds, letters to key officials, and public statements we kept pressure on policymakers to condition relations with Colombia on meaningful human rights improvements.