At the Center City firm of Hangley Aronchick Segal Pudlin & Schiller, a changing of the guard is underway.

After more than 20 years under the leadership of the firm's founders, partners voted recently to turn over the reins to Ron Schiller, a prominent insurance and commercial litigator who joined Hangley Aronchick in 2009 from global powerhouse DLA Piper.

While founders William Hangley and Mark Aronchick remain deeply involved in their practices and firm management, the firm said, the move signifies the advent of the next generation of leaders. Schiller succeeds Aronchick as chair.

Schiller said he anticipated little change and said the firm would continue on a path of modest growth, seeking high-quality lateral hires to augment its substantial litigation practice. Hangley's litigation focus and track record in high-profile cases would bolster the firm in an ever-more-competitive market, he said.

"We live in a very challenging marketplace, much more challenging than it was 10 years ago," Schiller said, pointing out that corporate clients have kept tight controls on litigation spending.

Schiller, 57, who lives in Villanova with his wife but plans to move soon to Center City, where he was raised, said he came to Hangley Aronchick because DLA was so large and its client list so extensive that it became impossible to find new clients who didn't conflict with existing legal engagements. When he realized that his hands were tied in generating new business, he said, he made just one call, to Hangley Aronchick, and joined the firm a short time later.

Schiller said the firm will continue its outsize commitment to pro-bono work — it played a key role in the "kids for cash" case in Luzerne County, Pa., in which two county judges were convicted of sending juveniles to a detention facility in which they had a hidden financial interest. The firm also won notice litigating for gay-marriage rights, a case that was handled by Aronchick. Aronchick is now representing the city in a legal challenge by the beverage industry to Philadelphia's soda tax.

In a legal marketplace where firms seem under pressure to grow exponentially or find a sizable partner for an acquisition or merger, Hangley is content to remain a litigation-focused firm with about 50 lawyers. Schiller said he could imagine the firm growing by a dozen or more lawyers over the years, but added that the key is not  growth as much as keeping clients happy by winning cases.