The United States Anti-Doping Agency (USADA, ) is a non-profit, non-governmental 501(c)(3) organization and the national anti-doping organization (NADO) for the United States. To protect clean competition and the integrity of sport and prevent doping in the United States with a performance-enhancing substance, the USADA provides education, leads scientific initiatives, conducts testing, and oversees the results management process. Headquartered in Colorado Springs, Colorado, USADA is a signatory to the World Anti-Doping Code, which harmonizes anti-doping practices around the world and is widely considered the basis for the strongest and strictest anti-doping programs to prevent doping in sport. In 2001, USADA was recognized by the U.S. Congress as "the official anti-doping agency for Olympic, Pan American and Paralympic sport in the United States." While USADA is not a government entity, it is partly funded by the Office of National Drug Control Policy (ONDCP), with its remaining budget generated from contracts for anti-doping services with sport organizations, most notably the United States Olympic and Paralympic Committee (USOPC). The United States has also ratified the UNESCO International Convention against Doping in Sport, the first global international treaty against doping in sport, and largely relies on USADA to carry out this commitment. The Chief Executive Officer of USADA, since September 2007, is Travis Tygart. History In October 1999, the USOC launched USADA and operations began on October 1, 2000. In 2003, one of USADA's first major undertakings was the revision of the then-current United States anti-doping policies in order to bring them into compliance with the newly adopted World Anti-Doping Code. One of the major adjustments made to the Code by USADA included reducing the standard of proof required in doping-related adjudication. Before modifications, the standard of proof was equal to that required in a United States court of law. After modification, USADA reduced the standard required to establish a doping violation to "comfortable satisfaction of a hearing body". Currently, USADA's status and independence from the USOC contrasts the norm in sport in the United States, as most professional sport organizations (MLB, NFL, NBA, NHL) manage the anti-doping functions of their own sports. As a result of USADA's ongoing multi-year contracts with the USOC and the sport national governing bodies (USA Track & Field, USA Cycling, USA Swimming, US Soccer, etc.), the agency is responsible for managing anti-doping programs, including testing and results in management, for each sport's athletes and events throughout the year.