Decades after studying existentialism in college, one of Chicago’s best-known retail brokers is making the ultimate expression of real estate individualism: forming his own brokerage.

Greg Kirsch has left Cushman & Wakefield, where he was the Midwest retail leader, to launch brokerage Kirsch Agency.

Leading a boutique retail leasing firm is a return to working in smaller shops early in his career, which Kirsch said were some of the most fun years he’s had after being part of a large, publicly traded brokerage for the past five years.

“I like the leanness and being an entrepreneur,” Kirsch told CoStar News. “The larger companies are amazing, and they provide incredible resources and connectivity, but I’m going back to the period in my career that I felt the most empowered to serve my clients and innovate the way I want to.

“The second part of it is, some of the people I respect the most tend to put their name on the door, like David Stone in Chicago and Robert Futterman in New York. I’m 53. This is probably my last shot to do this. I probably have the right energy and experience to do this now.”

Kirsch is managing broker of the Chicago-based firm, which will operate without an office. Former Cushman & Wakefield colleague Corey Black is the firm’s senior broker.

Kirsch is founding his own firm after a quarter-century working for brokerages large and small and representing owners of famous Magnificent Mile buildings such as the former John Hancock Center and the Wrigley Building.

Signature deals have included representing Under Armour in a nearly 30,000-square-foot flagship deal at 600 N. Michigan Ave. and advising now-defunct bank Washington Mutual on a wave of 186 leases signed in the Chicago area in less than two years.

It’s unclear who will fill Kirsch’s Midwest leadership role at Cushman & Wakefield. A spokesman for the Chicago-based firm declined to comment to CoStar News.

Kirsch earned a law degree from Chicago-Kent College of Law and began his career as an insurance-industry lawyer before becoming an office broker at Insignia/ESG, which later merged with CBRE. Kirsch later shifted to a retail focus at firms including Baum Realty and Newmark.

He said the latest career move could be traced even further back when Kirsch studied existentialism as a philosophy major at Loyola University Chicago.

“Existentialism is about valuing your worth every day,” Kirsch said. “Being a broker is an exploration of your worth every day. Running a company is the ultimate form of self-sufficiency.

“I will tell a client not to do a deal if it’s bad for their brand, even though it costs me a commission. The validation is helping your clients each day.”