USADA says that two, three-member arbitration panels determined Salazar and Jeffrey Brown, a Texas endocrinologist who treated many of Salazar's athletes, should be banned for "orchestrating and facilitating prohibited doping conduct."
Top athletics coach Alberto Salazar, who has guided star Olympians such as Mo Farah and Galen Rupp, has been slapped with a four-year ban after being found guilty of doping violations.
The decision to ban the 61-year-old from the sport comes after a four-year investigation by the United States Anti-Doping Agency and prolonged battle behind closed doors.
USADA also said Jeffrey Brown, a Texas endocrinologist who treated many of Salazar's athletes, has also been given a four-year suspension.
In announcing the bans, USADA praised the athletes for speaking out.
"The athletes in these cases found the courage to speak out and ultimately exposed the truth," said USADA chief executive Travis Tygart.
"While acting in connection with the Nike Oregon Project, Mr. Salazar and Dr. Brown demonstrated that winning was more important than the health and wellbeing of the athletes they were sworn to protect."
USADA said in the statement that two, three-member arbitration panels had determined Salazar and Brown should be banned for "orchestrating and facilitating prohibited doping conduct."
The Cuban-born Salazar operates the Nike Oregon Project – which four-time Olympic champion Farah belonged to from 2011 until 2017.
Salazar was discovered to have trafficked or attempted to traffic banned substance testosterone, given athletes a substance in excess of its permitted limit and tampered with the doping control process of athletes.
"USADA's investigation yielded a wide range of evidence referenced in the hearing, including eye-witness proof, testimonies, contemporaneous emails, and patient records," USADA said in a news release.
"Between the two cases, USADA relied on more than 2,000 exhibits, which the AAA heard along with the defendants' cases. In all, the proceedings included 30 witnesses and 5,780 pages of transcripts."
Farah left Salazar's camp in 2017 but denied the decision was related to Oregon Project doping accusations.
Salazar is believed to be in Doha where several Oregon Project athletes are competing in the World Track and Field Championships.
He has repeatedly denied the charges.