The cornerback-kick returner was suspended all last season, when he was with the Tennessee Titans, because of an accumulation of arrests and legal problems. He was traded to the Cowboys in April, then was allowed in June by commissioner Roger Goodell to join the team in training camp and in preseason games.
Goodell, however, was still waiting to decide whether to let Jones play in the regular season. That news came Thursday, hours before Dallas' final preseason game.
"It feels good man, you know, to get a second chance and I just have to take advantage of it," Jones told The Dallas Morning News. "First and foremost, I don't want to let myself down, definitely my little girl down. I'm thankful for [Cowboys owner] Jerry [Jones], the fans in Dallas and my teammates for believing in me. I need to keep doing what I've been doing to get reinstated, staying with myself and my teammates and staying away from those knuckleheads and just stay focused."
"This is another step in the process," Jones said in a statement released by the Cowboys. "I am very grateful for this opportunity, and I understand my responsibilities to the Dallas Cowboys and the National Football League. Right now I just want to keep working hard so I can accomplish the goals that I have set for myself both on and off the field."
Since being cleared almost three months ago by commissioner Roger Goodell to practice with the Cowboys, Jones had repeatedly expressed confidence that he would be reinstated for the season and said he was doing everything expected of him.
Still, there was a sense of relief when he finally received the official news -- in a phone call while walking in a parking lot.
"I am fully a Dallas Cowboy," Jones proclaimed before the last preseason game. "I don't have it lingering over my head, will he get reinstated, will he not get reinstated. I just have to keep myself out of bad situations like I have been doing the last six or seven months.
"I did scream. Immediately I called my mom, because I've been beating myself up, but my mom has been through this roller-coaster with me."
Jones received partial reinstatement to the NFL on June 2 from Goodell and as part of his reinstatement was permitted to participate in organized team activities as well as training camp and preseason games.
While that decision gave Jones the chance to earn his way back into the league, Goodell didn't guarantee he would be reinstated.
News of Jones' reinstatement came hours before Dallas' final preseason game against Minnesota, when Jones and the expected Cowboys starters didn't even play. Jones wore his No. 21 jersey and shorts on the sideline.
Jones was suspended in April 2007 following an accumulation of arrests and legal problems, including his connection to a shooting at a Las Vegas strip club. He's been arrested six times and involved in 12 incidents requiring police intervention since being drafted in the first round by Tennessee in 2005.
Police said Jones "instigated" a brawl inside the club by showering strippers on stage with dollar bills from a large plastic trash bag.
Jones was charged with two felony counts of coercion stemming from allegations that he threatened to kill club employees and scuffled with a bar bouncer. He was never charged in the shooting, which paralyzed a club employee.
Jones missed all of last season under the player conduct policy and could miss all or part of the 2008 season if he has another incident.
Since being traded to the Cowboys, Jones has tried to surround himself with a better support group. He's befriended former Cowboys Michael Irvin and Deion Sanders. Jones has also become friends with several of his new teammates, including Tank Johnson, whom the Cowboys helped return from a similar suspension last season.
"Adam has worked hard to get to this point, but he also knows that there is still a lot of work ahead of him," Jerry Jones said. "He is fully aware of the opportunity that he has been given, and he knows that this is an ongoing process."
NFL spokesman Greg Aiello wrote in an e-mail that Goodell wouldn't have a comment Thursday regarding the reinstatement.
Jones said he spoke to Aiello, but not the commissioner. The cornerback said he got congratulatory text messages from most of his teammates once word of his reinstatement spread.
There are past mistakes that Jones knows he can't repeat, especially off the field.
"I have to conduct myself like an NFL player to make sure none of these actions come again," Jones said. "I work hard every day to make sure I don't make the same mistakes. Can I say I would never ever make the same mistakes? No, I can't say that. I'll make sure I put myself in way better situations than I have put myself in the past."
Jones said that includes "surrounding myself around the right people and staying out of gentlemen's clubs, having a great relationship with God and spending more time with my family."
Two weeks ago, Jones sent a letter to Goodell asking to be cleared for the regular season, and saying he would stay out of trouble. Jones knows he has to if he wants to stay in the NFL.
"I think from the beginning there were a lot of critics saying that this couldn't be done, that he couldn't turn his life around," said Jones' agent and attorney, Manny Arora. "He's proven everyone wrong. He's got a very bright personal and professional future."
Jones had said repeatedly since being cleared almost three months ago to practice that he was confident that he would be reinstated for the regular season and that he was doing everything expected of him.
Still, there was a sense of relief when he got the official news.
"There's no sure thing in life. It's nice to finally get the affirmation for all the hard work he's put in," Arora said, after speaking to Jones. "The rest is up to him. It's time to play football. He's a very motivated player. I think he's matured greatly through this. He has a good head on his shoulders. He should be fine."
Jones played in the first three preseason games, making his first start for the Cowboys last Friday. He was at left corner in place of injured Pro Bowler Terence Newman after rookie Mike Jenkins started the first two games. Jones had eight tackles and a pass deflection in those three games.
Newman (groin) is expected to be back for the Sept. 7 opener at Cleveland, but Jones will still be a prominent player on passing downs and special teams. Jones had punt returns of 18 and 24 yards during the preseason, and coach Wade Phillips said this week that he was considering Jones for kickoff returns because of injuries in that spot.
The Cowboys had been operating under the assumption that Jones would indeed be reinstated for the season. Jones' involvement in different schemes increased throughout camp as he got comfortable in the system.
After Jones first joined the team for practice in June, he said he had owned up to his bad decisions and was focused on the future and getting back into the game after more than a year off the field.
"Being human, it changed him a lot. It was a very difficult process to go through," Arora said. "He took responsibility for everything and overcame it."
Information from The Associated Press was used in this report.