T. Weiss Realty began as a commercial real estate business founded in 1969 and grew from early retail properties into a company focused on office development on Long Island. The firm develops, leases, and manages Class-A commercial office space, with a business model centered on owning and operating its properties while providing flexible lease terms, built-to-suit space, and tenant support services. Its portfolio and market presence are tied to Suffolk County and the broader Long Island office market, where the company serves a range of tenants from smaller businesses to larger corporate users. T. Weiss Realty also extends its activity into construction and tenant improvements through an in-house construction arm, supporting renovations and new office build-outs across its properties.