A statement by the NFL Thursday said Williams would be allowed back into the league and that Commissioner Roger Goodell had approved a contract Williams signed with the Titans as a defensive senior assistant.
"The commissioner cited several reasons for the reinstatement, including Williams' forthcoming acknowledgement of and acceptance of responsibility for his role in the bounty program at the Saints, his commitment to never again be involved in a pay-for-performance or bounty system and his pledge to teach safe play and respect for the rules at all levels of the game," the NFL statement read.
"The commissioner emphasized that Williams must fully conform to league rules and will be subject to periodic monitoring to confirm his compliance."
Williams was suspended indefinitely last March by Goodell after an internal investigation indicated Williams, as the Saints' defensive coordinator, ran a bounty program that allegedly paid players for injuring opponents.
New Orleans Coach Sean Payton recently was reinstated by Goodell after nearly a year away from the team. Other team officials and players were also suspended.
The NFL claimed that Williams was responsible to a program in which Saints players contributed money, with cash paid for good defensive players, including interceptions but also for causing injuries to opposing players.