Wiggins is believed to have accepted a guarantee of $335,000, fitting into the Sixers' salary-cap slot created when they traded backup forward Bob Thornton to Minnesota last season in return for a second-round draft choice.
Wiggins has spent five seasons in the NBA, one with Chicago and five with with the Rockets. He was disqualified from the league during the 1986-87 season under the rules of the anti-drug abuse program, but was reinstated in time to play for the Rockets in '89-90. He did not play at all last season.
"I can't play basketball for the rest of my life, but this (following the provisions of his after-care program) is something I have to do the rest of my life. I do it each day, then get up the next day and do it again. But the longer you do it, the easier it becomes."
The Sixers zeroed in on Wiggins last season while Wiggins was working out on his own in Toronto.
"The first step was the constant contact," Sixers owner Harold Katz said. ''I knew what he was doing; we knew he could play. But seeing it is believing it, and I told him that if he came this summer and showed us he was in condition, that he could still play, that we would sign him. Well, he showed us."
Wiggins said the reality of the moment was driven home when he signed the contract Thursday in Monticello, N.Y., where the team played two exhibitions against New York.
"I was very nervous then," he said. "That was when I knew I was all the way back. Riding back to Philadelphia, though, I began to think about (last night's) press conference and I know that there are some people - placed in that situation - who just lose themselves, say the wrong thing. But once it started, I found that I was very comfortable.
"I just felt I had to come here and prove myself - continue to prove myself - show that I'm a good player, a good citizen. I have two kids and a wife, and I have to do it for them. I tried to do it for myself in the past, and I've come up short."
Katz said Wiggins has shown a sincerity that touched him.
"I like Mitchell," Katz said. "You meet somebody, whether it's over the phone or in person, and you take a liking. This was the only place he wanted to come, and I think that was because we showed the interest. I think he needed that. We have no doubt that he'll help us."
There is a risk involved, but the Sixers know that if Wiggins falters in his after-care program, he would be banned from the league for life and that they would be relieved of their financial obligation.
"We - society - owe people a second chance," Katz said. "Mitchell's a big boy. If he doesn't do it, shame on Mitchell."