WASHINGTON, D.C., July 01, 2004 - Cogent Communications Group, Inc. (AMEX: COI), a multinational Tier One, optical Internet service provider, announced today that Reed Harrison will become its President and Chief Operating Officer. He brings to Cogent over 30 years of experience in business, operations, and technical leadership roles during a broad and successful career, most recently as AT&T's Senior Vice President - Network Engineering & Operations. "We are fortunate and pleased to have Reed, a seasoned telecommunications executive with deep industry knowledge, experience, and strategic vision join Cogent's management team," said Dave Schaeffer, Cogent Communications CEO. Harrison will be responsible for Cogent's day-to-day operations. He will work closely with Schaeffer and Cogent's Board of Directors to implement and refine the company's strategies.

About Cogent Communications

Cogent is a facilities-based provider of low-cost, high-speed Internet access and Internet Protocol, or IP, connectivity in North America and Europe. Cogent Communications' global headquarters is located at 1015 31st Street, NW, Washington, D.C. 20007.

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Information in this release may involve expectations, beliefs, plans, intentions or strategies regarding the future. These forward-looking statements involve risks and uncertainties. All forward-looking statements included in this release are based upon information available to Cogent Communications Group, Inc. as of the date of the release, and we assume no obligation to update any such forward-looking statement. The statements in this release are not guarantees of future performance and actual results could differ materially from our current expectations. Numerous factors could cause or contribute to such differences. Some of the factors and risks associated with our business are discussed in Cogent's registration statements filed with the Securities and Exchange Commission and in its other reports filed from time to time with the SEC.

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