"Ballard was always one of the best law firms in Philadelphia and its profile and strength as a national firm are greater than ever before," Rendell said in the release. "This is a great time to be coming back and I look forward to contributing to the firm's growth and stature."
Prominent law firms would want a former governor as a partner for prestige and for his ability to make contacts that may drum up business for the firm.
Arthur Makadon, the firm's chairman, said that Rendell's personality and leadership traits would make him a good match for the firm.
"The traits that made Ed such an effective leader in the public sector - grit, intellect and personal magnetism - will make him just as effective in the private sector representing clients of the firm and helping new clients," Makadon said.
During Rendell's previous time at Ballard, he earned $254,000, for which he told reporters that he had done "practically nothing."
Makadon told the Philadelphia Business Journal that the firm will put Rendell to more use now, saying that "this time around we have a real plan to use him, and the last time he was here we really had no plan and nothing really happened."
The Ballard job is one of a number of ways Rendell is keeping himself busy.
He said Friday that he'll work part time as a visiting fellow at the Brookings Institution, a Washington think tank. He is shopping around for work as a paid cable-TV commentator, and he has indicated that he's finishing a book. Rendell has retained the William Morris Agency to help him with these ventures.
Rendell has said that he also plans to spend more time on Building America's Future, a bipartisan coalition focused on infrastructure that he founded with New York City Mayor Michael Bloomberg and former California Gov. Arnold Schwarzenegger.
Rendell also is expected to continue to serve on the boards of nonprofit organizations, according to the Ballard announcement, as well as to continue teaching at the University of Pennsylvania.