Iron Mountain Incorporated and Tumbleweed Communications Corp. Combine Strengths To Offer New Standard In Electronic Data Archiving

Millions of Messages Per Day Can Be Archived By New Iron Mountain/Tumbleweed Solutions

BOSTON, MA and REDWOOD CITY, CA - September 27, 2000 - Iron Mountain Incorporated (NYSE:IRM), the global leader in records and information management services, and Tumbleweed® Communications Corp. (Nasdaq:TMWD), a leading provider of Internet infrastructure for business messaging, today announced a comprehensive strategic alliance to jointly develop, market and sell new products and services for electronic data archiving.

"Our customers want to leverage the secure communications and management infrastructure they have built with Tumbleweed solutions. Electronic archiving services are the natural next step," said Jeffrey C. Smith, President and CEO of Tumbleweed Communications Corp. "With unmatched industry knowledge and the country's largest customer base, Iron Mountain is the ideal partner for Tumbleweed. Iron Mountain is moving aggressively to leverage its significant expertise in physical archiving to define an efficient, cost-effective, high quality solution for electronic archiving for each of its customers. The millions of messages and documents that flow through Tumbleweed's pipes every day can easily be routed to electronic archives - to Iron Mountain archives. We believe that the collaboration between Iron Mountain and Tumbleweed will deliver the industry's most compelling electronic data archiving products and services."

"Tumbleweed's applications are proven - and it is these applications that will drive data into our electronic archives. Today, Tumbleweed is installed at more than 800 enterprises, including some of the world's largest companies, managing the electronic communications stream and archiving millions of email messages a day," said C. Richard Reese, Chairman and Chief Executive Officer of Iron Mountain Incorporated. "Iron Mountain has been seeking a partner who has successfully deployed the solutions major enterprises use to manage and archive electronic communications, one who delivers the applications that drive this vital communications channel. We are delighted to join forces with Tumbleweed to build a new standard for electronic data archiving, and to offer it to our customers worldwide."

The Iron Mountain/Tumbleweed solution will integrate with Tumbleweed Messaging Management System (MMS™), a set of email management products and services that enables enterprises to protect valuable corporate information on the Internet. With MMS, Tumbleweed can centrally create policies to manage and control Internet communication without requiring end users to change either their email clients or their business practices. MMS Enterprise Archiving automatically archives all or selected email messages to create a complete, indexed record for internal or governmental review.

Iron Mountain and Tumbleweed will jointly fund future development to enhance the Iron Mountain/Tumbleweed archiving capabilities. Companies who deploy the Iron Mountain/Tumbleweed solution can choose to host their archives either on-site or outsource them to Iron Mountain and Tumbleweed.

About Iron Mountain Incorporated
Iron Mountain Incorporated (NYSE: IRM) is the global leader in records and information management services. Iron Mountain currently provides services to over 120,000 customer accounts, including more than half of the Fortune 500, in 77 markets in the United States and 37 markets outside of the United States. The Company operates over 600 records management facilities in North America, Europe and Latin America. This alliance with Tumbleweed is part of Iron Mountain's continuing strategy to expand into new digital-based services to complement its core businesses. For more information about our products and services, visit Iron Mountain's web site at http://www.ironmountain.com.

About Tumbleweed Communications Corp.
Tumbleweed is a leading provider of solutions for managing secure communication and collaboration to enable the business Internet. Tumbleweed's robust policy-based framework empowers organizations to safely share and protect critical information, increase customer loyalty and privacy and dramatically reduce costs. Tumbleweed is trusted by 1,000 blue-chip customers including American Express, Chevron, Datek Online, the European Union's Joint Research Council, First Union Wachovia, John Deere, Merrill Lynch, Nike, Northern Trust, NTT, Salomon Smith Barney, Travelers and US Food and Drug Administration. One hundred of the Fortune 500 are Tumbleweed customers. Tumbleweed Communications was founded in 1993 and is headquartered in Redwood City, Calif., with offices around the world.

Except for the historical information contained herein, the matters discussed in this press release may constitute forward-looking statements that involve risks and uncertainties that could cause actual results to differ materially from those projected, particularly with respect to the security features of Tumbleweed's products and the activities of any third party. In some cases, forward-looking statements can be identified by terminology such as "may," "will," "should," "potential," "continue," "expects," "anticipates," "intends," "plans," "believes," "estimates," and similar expressions. For further cautions about the risks of investing in Tumbleweed, we refer you to the documents Tumbleweed files from time to time with the Securities and Exchange Commission, particularly Tumbleweed's Form 10-K filed March 30, 2001 and Form 10-Q filed November 13, 2001. Tumbleweed assumes no obligation to update information contained in this press release.