SL Green Realty Corp. operates as a real estate investment trust. The firm engages in the acquisition, development, ownership, management and operation of commercial and residential real estate properties. It operates through the Real Estate, and Debt and Preferred Equity Investments business segments. The Real Estate segment consists of security, maintenance, utility costs, real estate taxes, and at certain properties ground rent expense. The Debt and Preferred Equity Investments segment includes cash flow from operations, cash on hand, and other forms of secured or unsecured financing. The company was founded by Stephen L. Green in June 1997 and is headquartered in New York, NY.