The Mavericks announced the deal with the 14-year veteran on Wednesday. His contract is for the veteran minimum.
Dallas originally acquired Harris from Washington, along with Jerry Stackhouse and Christian Laettner, in a draft-day trade for Antawn Jamison in June 2004. He played for the Mavericks until getting traded to New Jersey in February 2008, in a deal that brought Jason Kidd to the Mavericks.
Harris first returned to Dallas as a free agent before the 2013-14 season, and stayed until the Mavericks traded him to Denver last February as part of a three-team deal at the trade deadline.
The 35-year-old Harris has averaged 11.1 points, 4.1 assists and 1.1 steals in his 917 career games, including 446 starts.