SL Green Realty Promotes Harrison Sitomer To President

2 March 2026

SL Green promoted its young, fast-rising head of investments to Marc Holliday’s second-in-command.

New York’s biggest commercial landlord on Monday named Harrison Sitomer, 36, president of the $2.6 billion REIT.

“Harry exemplifies the dedication, tenacity and strength that define SL Green,” Holliday, SL Green’s CEO and chairman, said in an announcement. “This promotion reflects his achievements and our continued commitment to growing talent from within.”

Sitomer will retain his title as chief investment officer.

The move formalizes Sitomer’s growing role at the company, where he’s risen through the ranks since starting out as an intern in 2011.

The University of Pennsylvania graduate began as an analyst and worked his way up through the investment side of the business, where he got his big break thanks to a bit of fortuitousness.

In 2020 then co-CIO, Isaac Zion, left the company after 13 years. And less than a year after that the other co-CIO, David Schonbraun, also left.

SL Green in 2022 named Sitomer as the new chief investment officer, Holliday’s initial role when he joined the company in 1998.

In that job, Sitomer oversaw deals like SL Green’s takeover of 245 Park Avenue out of bankruptcy and its $445 million acquisition of 450 Park Avenue, which at the time was the REIT’s first purchase in four years.

He also had a heavy hand in building the company’s $1.3 billion debt fund and growing its asset management business, taking on more responsibilities normally under the purview of a company president.

SL Green has been without an official president since 25-year company veteran Andrew Mathias stepped down when his contract expired at the end of 2024. The move was largely seen as a cost-savings measure for the REIT, which had been beaten down by the pandemic and work-from-home.

Sitomer is now tasked with overseeing SL Green’s $2.5 billion in planned asset sales, as well as growing its management business. His ascension also makes him a natural candidate to succeed Holliday if and when he decides to step aside.

Holliday noted how impressive it was to see Sitomer grow “from an intern into a leader.”

“His entire career has been shaped here, and his commitment to our culture, our stakeholders and our city is unwavering,” he said.