White and Williams managing partner Guy Cellucci died in his sleep early Saturday morning. He was 59 years old.

Cellucci took over as managing partner of the firm in November 2010 after spending more than a decade leading the 230-lawyer firm’s litigation department.

The firm’s nine-person executive committee, of which Cellucci was the chairman, met Saturday to discuss how the firm would operate moving forward.

Ken Gibb, White and Williams’ executive director, will be the leader in charge of all administrative matters until a new chairperson can be named. That is the process as outlined in the firm’s partnership agreement. A spokeswoman for the firm said the committee has agreed not to discuss firm matters in any more detail until after Cellucci’s funeral.

“Guy was an outstanding leader and has left the firm in good working order,” Gibb said in a statement. “We will continue with the leadership that Guy put in place and discuss next steps in the near future.”

Cellucci started with White and Williams out of law school and recently celebrated his 34th anniversary, having spent his entire legal career at the firm. While he began his career practicing general commercial litigation, he quickly focused on insurance coverage cases, particularly those involving environmental liabilities.

Cellucci put himself through college working at the Breyers ice cream factory, the firm said. He was a 1976 graduate of St. Joseph’s University and a 1979 graduate of Georgetown Law School. He became a partner at the firm in 1986 and in 1999 he became chair of the commercial litigation department.

“Notwithstanding his rise in leadership, Guy always had an open door,” the firm said. “He would strategize on cases even if he was not involved in them and would mentor younger attorneys.”

“He was always willing to discuss anything that was on someone’s mind, personal or professional; he always made time,” said Michael Olsan, chairman of the reinsurance practice group, in a statement.

Gibb said in an interview Monday that he handled the administrative side of running the firm while Cellucci handled the legal aspects. Cellucci was able to look at an issue from all angles and quickly come up with a solution.

“I don’t think we ever had a meeting that lasted more than 15 minutes,” Gibb said, adding Cellucci’s clients looked to him for that same quick, thoughtful approach to their problems.

Cellucci maintained an active practice while leading the firm. In fact, he was in the firm’s New York office Friday working on a matter, Gibb said. As active as he was with clients, Cellucci took equally to firm leadership.

“He loved the administrative side as much as the lawyering side,” Gibb said. “It was kind of a natural for him.”

Gibb described Cellucci as “extremely intelligent,” and a “wonderful and pleasant person” who was fair and a good listener.

Gibb said Cellucci was competitive and active and always going to the gym. He said word of Cellucci’s death was the last news he expected to hear Saturday morning.

Aside from his law firm life, Cellucci was an even more involved family man. Gibb said Cellucci was big on work-life balance, missing less than a handful of his daughter’s field hockey games her entire collegiate career. His daughter is set to be married next year and had just shown her father her wedding dress, Gibb said.

“He was involved in planning the wedding more than any man I have ever known,” Gibb said of Cellucci.

Cellucci is survived by his wife, Bernadette, and three children, Dan, Megan and Rob.

“He was an immensely talented, yet humble individual with a courageous desire to make the world a better place for his work associates, friends and family,” his son, Dan, said in a statement. “We will all miss him dearly.”

Outside of work, Cellucci enjoyed spending time in Avalon, N.J., golfing whenever possible, and was an avid Eagles and Penn State football fan, according to the firm.

Cellucci’s viewing is from 6 to 9 p.m. Thursday and from 9:30 to 10:30 a.m. Friday at SS Simon & Jude Church, Route 352 and West Chester Pike, West Chester, Pa. His funeral Mass will follow at 10:30 a.m. Interment is at SS Peter & Paul Cemetery.

Contributions in his memory can be made to La Salle Academy, 1434 N. Second St., Philadelphia, PA 19122.

Gina Passarella can be contacted at 215-557-2494 or at gpassarella@alm.com. Follow her on Twitter @GPassarellaTLI.