Trane, Inc. Signs Full Building Lease Renewal with Prime Group Realty Trust at 7100 Madison Street in Willowbrook, Illinois

Business Wire, April 11, 2008

CHICAGO -- Prime Group Realty Trust (NYSE: PGEPRB), a Chicago-based real estate investment trust ("PGRT" and the "Company"), announced that Trane, Inc. renewed its full building, 50,157-square-foot lease at 7100 Madison Street in Willowbrook, Ill.

Profiled by its two brand names Trane[R] and American Standard[R], Trane (www.trane.com) is a leading worldwide provider of a broad range of energy-efficient heating, ventilation, and air conditioning (HVAC) systems. Its Chicago-area office has implemented energy saving solutions for prominent clients such as the DuPage County Governmental Complex, East Maine School District, Hartford Plaza in downtown Chicago, and the Windy Point Office Building in Schaumburg, Ill.

Hugh Williams of Cushman & Wakefield represented the tenant while Julie Mertins, assistant vice president of leasing for Prime Group Realty Trust, represented the landlord. "Trane has been a highly respected industry leader for decades and a long-term, model tenant," said Mertins. "The 7100 Madison Street building provides the company with a great location to provide services and support to its Chicago area clientele."

About Prime Group Realty Trust

Owned by one of the largest private real estate owners in the country, The Lightstone Group, Prime Group Realty Trust is a fully-integrated, self-administered, and self-managed real estate investment trust (REIT) which owns, manages, leases, develops, and redevelops office and industrial real estate, primarily in metropolitan Chicago. The Company owns 9 office properties containing an aggregate of 3.4 million net rentable square feet, one industrial property comprised of approximately 120,000 square feet, a joint venture interest in one office property comprised of approximately 101,000 net rentable square feet and a membership interest in an unconsolidated entity which owns extended-stay hotel properties. It leases and manages approximately 3.5 million square feet comprising all of the wholly-owned properties. In addition, the Company is also the managing and leasing agent for the approximately 959,000 square foot property located at 77 West Wacker Drive in Chicago, Illinois, and the approximately 1.5 million square foot Citadel Center office building located at 131 South Dearborn Street in Chicago, Illinois. For more information about Prime Group Realty Trust, contact the company's Chicago headquarters at (312) 917-1300 or visit its website at www.pgrt.com.

About the Lightstone Group

The Lightstone Group is one of the country's largest privately held real estate companies with interests in residential, office, retail, hospitality, and industrial real estate assets. The company, principally through its related operating entities, Prime Retail, Extended Stay Hotels, and Prime Group Realty Trust, owns a diversified portfolio of over 687 hotels, 18,000 residential units and approximately 29 million square feet of office, industrial and retail properties in 46 states, the District of Columbia, Canada and Puerto Rico. Headquartered in New York, The Lightstone Group employs approximately 14,000 staff and professionals and maintains regional offices in Maryland, South Carolina, Illinois and New Jersey. For more information on The Lightstone Group, call 800-347-4078 or visit www.lightstonegroup.com.

Certain statements contained in this press release may constitute "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 that reflect management's current views with respect to future events and financial performance. The words, "believes," "expects," "anticipates," "estimates," and similar words or expressions are generally intended to identify forward-looking statements. Actual results may differ materially from those expected because of various risks and uncertainties, including, but not limited to, changes in general economic conditions, adverse changes in real estate markets as well as other risks and uncertainties included from time to time in the Company's filings with the Securities and Exchange Commission.