ALBANY — In the Spitzer administration, Lloyd Constantine has the title of senior adviser, but his business card might as well say “elder statesman.”

After making a fortune as an antitrust litigator, Mr. Constantine, 59, is once again a New York public servant, working together in government with Mr. Spitzer for the first time since the summer of 1982. Back then, Mr. Constantine was assistant attorney general under Robert Abrams and the future governor was his law school intern.

It was under Mr. Constantine’s tutelage, Mr. Spitzer said in a telephone interview with The New York Sun, that the man who is now governor “understood the texture of what state lawyering could accomplish” and the promise of the doctrine of “new federalism” that underpinned much of Mr. Spitzer’s work as attorney general. A quarter of a century later, their roles have reversed — Mr. Constantine now reports to Mr. Spitzer, who chose him for a job with a title that is purposefully ambiguous. “My role is sui generis. I’m sort of a monster man. I’m kind of a rover,” Mr. Constantine said in a recent interview.

Aides say Mr. Constantine, who will be dividing time between Albany and the city, is the big-picture guy who lays low in senior staff meetings until dispensing advice. He’s the person Mr. Spitzer is most closely relying on for governing expertise. He is the one, for instance, who insisted that the transition team not exclude leftover Pataki officials in policy discussions.

Mr. Spitzer told the Sun that Mr. Constantine is “someone I’ll ask to dig into tough issues that require creative thinking, fact-gathering, and a new approach.”

The first assignment the governor handed to his friend is to enter the political minefield of workers compensation and figure out a way to cut costs and increase benefits, while somehow satisfying both the unions and the business community.

Another one of his jobs is to take a sickle to outmoded agencies and offices. “There are 28 different agencies that have an economic development component,” he said. “Maybe that should be reduced to something less than 28.” Most of the problems he has come across, he said, are generations old, exculpating Governor Pataki. “Certain things never made sense and don’t make any sense,” he said, asking why would one design the Tappan Zee Bridge, which connects Rockland and Westchester counties, to last only 50 years. Eight years ago, Mr. Spitzer asked Mr. Constantine to be his headhunter in the attorney general’s office. Mr. Constantine roped in top-flight lawyers, particularly Dietrich Snell and Michele Hirshman, who would oversee Mr. Spitzer’s best-known cases. Mr. Constantine, whose antitrust commercial litigation firm was prospering, declined a second tour of duty in the attorney general’s office. He went on to be the lead counsel for the plaintiffs in the Visa Check/MasterMoney antitrust case that resulted in a $3.4 billion settlement. “It was a different moment for him in terms of his career as well as for mine,” Mr. Spitzer said.

Mr. Constantine knew there was a good chance Mr. Spitzer would be elected governor and began preparing his firm for his departure without making up his mind. The new job takes some getting used to even aside from the pay cut. Mr. Constantine’s favorite Albany restaurant was Keeler’s steakhouse, which disappeared decades ago. He now has to wear a holstered BlackBerry and, like almost every executive chamber employee, a blue security card band around his dress shirts, which are elegantly embroidered with “LC” on the cuffs. He has trouble finding his way around the endless underground plaza concourse.

Some things don’t change, like the hours. One night this week, Mr. Spitzer and his wife hosted some of his aides for an Executive Mansion dinner. The dinner ended at 10 p.m. and most people went back to the Capitol building for more work, Mr. Constantine said.

Mr. Constantine has a wiry frame, hair that doesn’t shake loose, and bushy eyebrows. A competitive squash and tennis player, he looks a decade younger than his 59 years and says he needs minimal sleep. He is most animated when he talks about the potential of Mr. Spitzer: “I think he’s a new type of statesman. He’s that much talkedabout but not frequently seen new statesman. He’s very pragmatic. He understands business. He understands money. He understands education. He really can’t be defined along pre-existing party or ideological lines. I sort of spotted this in him a while ago. I saw this in him very, very early on. I saw someone who had the stuff to be exactly where he is right now.”

Mr. Constantine decided he couldn’t miss it. He said, “I felt this moment would occur once in my life. It had never occurred before. It was unlikely to occur again, and I decided I wanted to be here when it was happening.”