Philadelphia's largest philanthropic foundation with primary focus on the region is undergoing another leadership transition. William Penn Foundation executive director Laura Sparks is stepping down to become president of the Cooper Union for the Advancement of Science and Art in New York, the foundation announced late Wednesday.

Sparks will remain with William Penn until sometime in the fall. At that point, Shawn McCaney, currently the foundation's director of creative communities and national initiatives, will take over as interim executive director while a permanent director is sought.

Sparks, 41, said that she was approached by a search firm and that it was Cooper Union's tradition of providing education without financial burden that attracted her to the job.

"I can't be more clear than to say that I'm enormously proud of the work we've done, enormously proud of the working relationship with the [Haas] family and their support for this work and their leadership in it," she said. "There are very few things that would have drawn me away from it. This happens to be one of them. It holds a special place in American history."

The William Penn Foundation funds education, the arts, public spaces, and the Delaware River Watershed and packs a big philanthropic wallop in the area. This year, it will disburse about $115 million in grants, said Janet Haas, chair of the foundation's board of directors.

In recent years, several executives have cycled in and out of the leadership position at the foundation, which had $2.3 billion in assets as of Dec 31.

Sparks assumed the top post in September 2014, when Peter J. Degnan stepped down after six months in the job.

Degnan, previously with the Wharton School, had been brought in after changes in grant guidelines and the sudden departure of Jeremy Nowak in 2012 after about a year and a half as head of the foundation. Nowak took over from Feather O. Houstoun, who resigned as president (as the position was then called) in 2011.

"We have had some transition over the years, no question," Haas said.

But she pointed out the longevity of grants managers and program directors who have stayed for decades, "so we've had lots of stability in the next level."

Of Sparks, Haas said: "We've had a wonderful working relationship, the family has treasured her, and we are really sad to see her go. But of course we support her. It's the next step in her career. We are so grateful for what she brought to the foundation."

Asked whether Sparks' departure signals other changes to come, Haas said: "No. There will be no changes to guidelines or giving priorities."

The foundation will search for a successor internally and externally, she said. "We are going to look for someone who embraces the strategic plan and this work, and who is smart, who challenges us, thinks a lot, reaches out in the community and nationally to attract resources to the Philadelphia region, and who operates from the sense of, what more can we do? Are we making sure that every dollar matters?"

Sparks officially starts at Cooper Union on Jan. 4. She will be its first female leader, the school said in an announcement.