Prime Group Realty Trust Announces that Continental Towers Earns the ENERGY STAR for Turning Energy Use into Savings

Business Wire, Sept 24, 2008

CHICAGO -- Prime Group Realty Trust (NYSE: PGEPRB) (the "Company"), announces that its Continental Towers office and retail complex in Rolling Meadows, Illinois has earned the U.S. Environmental Protection Agency's (EPA's) prestigious ENERGY STAR, the national symbol for protecting the environment through superior energy performance. Continental Towers joins approximately 3,200 projects nationwide that have earned the ENERGY STAR. Buildings earning the ENERGY STAR use about 35 percent less energy than average buildings, while still providing quality service and comfort to tenants.

"Prime Group Realty Trust is proud to accept EPA's ENERGY STAR," said Catherine Carlson, General Manager of Continental Towers. "Through this achievement, we have demonstrated our commitment to protecting the environment through energy efficient products and practices while also reducing our and our tenants' energy costs."

Three buildings in the Continental Towers complex were awarded the ENERGY STAR designation, Continental Towers One, Two and the Commercium. The fourth building in the complex, Continental Towers Three, will be eligible to receive the designation as additional new leases are consummated. Prime Group Realty Trust is also working actively toward earning the ENERGY STAR for the rest of its suburban portfolio. Continental Towers, conveniently located along the Northwest Tollway on Golf Road, is a Class A office complex, with retail amenities, consisting of 910,796 square feet and houses more than 40 businesses. Named in 2004, 2005 and 2006 as "The Office Building of the Year" for the Chicago Suburban market by the Building Owners and Managers Association (BOMA), Continental Towers continues to provide a stellar environment for the more than 2,000 employees who working the complex.

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 currently owns 9 office properties containing an aggregate of 3.4 million net rentable 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 552 extended-stay hotel properties in operation in 43 U.S. states consisting of approximately 59,000 rooms and three hotels in operation in Canada consisting of 500 rooms. It leases and manages approximately 3.4 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 known as The United Building 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.

This press release contains certain 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.