PRESS RELEASE DETAIL


Mar 13, 2008

CoStar Group To Report Financial Results for Fourth Quarter and Full-Year 2007

2008-01-30 2008 CoStar Group To Report Financial Results for Fourth Quarter and Full-Year 2007 Earnings Report To Be Issued After Market Close on Wednesday, February 2...

2008-01-30 2008 CoStar Group To Report Financial Results for Fourth Quarter and Full-Year 2007 Earnings Report To Be Issued After Market Close on Wednesday, February 20; Conference Call To Discuss 2007 Financial Results and the Company's Outlook for 2008 Scheduled for Thursday, February 21

BETHESDA, MD – January 30 , 2008 – CoStar Group, Inc. (Nasdaq: CSGP), the number one provider of information services to the commercial real estate industry, will report financial results for the fourth quarter and year ended December 31, 2007 after the market close on Wednesday, February 20, 2008. Management will conduct a conference call the following day, Thursday, February 21, 2008, at 11:00 a.m. Eastern Standard Time, to discuss the year-end financial results and the company's outlook for 2008.

To participate in the conference call, please dial 888-688-0419 from within the United States, or 706-634-0964 from outside the United States. Investors may also access a live audio web cast of this conference call by accessing the link on the investors section of CoStar Group's web site at www.CoStar.com.

An audio recording of the conference will be available for replay two hours after the call's completion and remain available through midnight on March 6, 2008. The  replay will also be available over the Internet at http://www.costar.com/corporate/investor/ for a period of time following the call. To access the recording, use the dial-in numbers and enter the Conference ID number listed below.

About CoStar Group,  Inc.

CoStar Group, Inc. (Nasdaq - CSGP) is the number one provider of information services to commercial real estate professionals in the United States as well as the United  Kingdom.  CoStar's suite of services offers customers access via the Internet to the most comprehensive database of commercial real  estate information throughout the U.S. as well as in the United  Kingdom and France.  Headquartered in Bethesda, MD, the company has approximately 1,300 employees, including the largest professional research organization in the industry.  For more information, visit www.costar.com.

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PRESS RELEASE ANNOUNCING YEAR-END 2007 FINANCIAL RESULTS:

After the market close on Wednesday, February 20, 2008

CONFERENCE CALL:
Thursday, February 21, 2008
11:00 AM – 12:00 Noon (EST)

Hosted by CoStar Group President & Chief Executive Officer
Andrew C. Florance and Chief Financial Officer Brian J. Radecki.

U.S. Dial-In Number:  (888) 688-0419
International Dial-In Number:  (706) 634-0964
Conference ID:  3344491

Live web broadcast can be found at: www.costar.com/corporate/investor/

CONFERENCE CALL REPLAY:
U.S. Dial-In Number:  (800) 642-1687
International Dial-In Number:  (706) 645-9291
Conference ID:  33444915

Contacts:
Analysts/Investors: Brian J. Radecki - Chief Financial  Officer (301) 664-9132 or bradecki@costar.com

Media: Timothy J. Trainor – Corporate Communications (301)  280-7695 or ttrainor@costar.com 

This news release  includes "forward-looking statements" including, without limitation,  statements regarding CoStar’s expectations, beliefs, intentions or strategies  regarding the future. These statements are subject to many risks and  uncertainties that could cause actual results to differ materially from these  statements. More information about potential factors that could cause actual  results to differ materially from those discussed in the forward-looking  statements include, but are not limited to, those stated in CoStar's filings  from time to time with the Securities and Exchange Commission, including  CoStar’s Form 10-K for the year ended December 31, 2006, under the heading  “Risk Factors” and CoStar Group’s Form 10-Q for the quarter ended September 30,  2007, under the heading “Risk Factors.” All forward-looking statements are  based on information available to CoStar on the date hereof, and CoStar assumes  no obligation to update such statements.
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