Southwestern Energy Appoints Steven Mueller as President and Chief Operating Officer

HOUSTON, May 20 /PRNewswire-FirstCall/ -- Southwestern Energy Company today announced the appointment of Steven L. Mueller as President and Chief Operating Officer effective as of June 2, 2008. Harold M. Korell will continue to serve as the Company's Chairman of the Board of Directors and Chief Executive Officer. Mr. Mueller will report to Mr. Korell and will be responsible for the company's oil and gas exploration and production business and its Midstream operations. A graduate of the Colorado School of Mines, Mr. Mueller has over 30 years of experience in the oil and gas industry and has served in multiple operational and managerial roles at Tenneco Oil Company, Fina Oil Company, American Exploration Company, Belco Oil & Gas Company, The Houston Exploration Company and CDX Gas, LLC.

"I have had the good fortune to work with Steve for several years while we were both at Tenneco and again at American Exploration, and I look forward to bringing his leadership and tremendous abilities in all facets of the business into Southwestern Energy," stated Harold M. Korell, Chairman and Chief Executive Officer of Southwestern. "Steve's addition strengthens our executive management team in a very positive way as we grow into the future."

Southwestern Energy Company is an independent energy company whose wholly-owned subsidiaries are engaged in oil and gas exploration and production, natural gas gathering and marketing and natural gas distribution. Additional information on the company can be found on the Internet at http://www.swn.com/.

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