Adu, only 17 but a 3-year MLS veteran, was introduced at a news conference in Salt Lake City Tuesday, saying: "I couldn't be happier. I cannot be happier to be here. It is something I wanted.
"I've had three great years in D.C. I enjoyed myself and learned a lot."
Adu scored 11 goals and had 17 assists for D.C. United and made the MLS All-Star team twice but was never entirely happy about his playing time.
He was traded Monday to Real Salt Lake along with the rights to goalkeeper Nick Rimando for the rights to goalkeeper Jay Nolly and undisclosed future considerations. That last clause reportedly includes a share of any replacement allocation given Real Salt Lake should Adu move to another league.