This report describes the progress toward “3 by 5,” the target that 3 million people with HIV in developing and transitional countries would be receiving antiretroviral treatment (ART) by 2005. The report discusses global efforts to increase access to ART and the reasons for the successes and failures. It highlights the progress and challenges in some countries and obstacles to scaling up ART and HIV prevention. It provides recommendations on ways to overcome the problems, including the need for high-level political commitment, financial sustainability, human resources and supply management, integrating treatment and prevention, equitable access and coordinating support and evaluation. The annexes include the estimate of the number of people on ART, treatment need and ART coverage, and a list of the 3 by 5 focus countries. Data indicate that almost 1 million people are receiving ART by the end of June, 2005.