New Study of Green Datacentre Trends Finds Increased Concern Over Regulations Across Europe

LONDON - New Digital Realty Trust survey reveals 70 percent of users concerned about Government regulation

An independent survey of senior datacentre professionals from across Europe carried out on behalf of Digital Realty Trust (NYSE: DLR), the world’s leading wholesale datacentre provider, has revealed heightened concerns about government regulation in the European datacentre industry. Nearly 70 percent of companies surveyed reported that they are extremely concerned or very concerned with the potential impact of Green regulations on data centres.

“This survey clearly shows that there is a high level of concern about the impact of Green regulations on datacentre facilities. While the new Carbon Reduction Commitment (CRC) regulations in the E.U. address a number of questions about the new rules, new concerns about how companies will achieve compliance have arisen. That uncertainty is reflected in these results in terms of how the new rules will impact operations, finance and customer relations,” said Jim Smith, CTO of Digital Realty Trust.

The survey is thought to be one of the most exhaustive to date across the European datacentre market. People surveyed were restricted to a minimum of Director level in IT, MIS, IS or finance and they needed to represent companies with either euro 500M or 500M pounds sterling annual revenues or 2,500+ employees. They also had to be responsible for managing a datacentre, implementing a new datacentre, executing contracts for a new datacentre or expanding existing datacentres. The survey was concluded at the end of March by Campos Research.

Other findings from the study include the following: - 60 percent of surveyed companies now have Green datacentre strategies in place - Over half (57 percent) felt there was now a clear definition of what constitutes a Green datacentre - Energy efficiency is viewed as the key criteria for a Green datacentre - While many mention a Green strategy as a factor in choosing a datacentre provider, no company emerges as a Green leader in the survey - Among companies that have a Green datacentre strategy, the qualities they are looking for in datacentre providers include: - Knowledge of current regulations and emerging Green standards - Experience building facilities with LEED or BREEAM certification - The ability to meet ISO 14001 and Green Grid standards - More than half (55%) would reject a provider with no Green strategy

While energy efficiency was seen as the dominant characteristic of a Green datacentre, recycled materials, carbon issues and transportation were nearly equally important to those surveyed, who also included targeted cooling, efficient UPS and metering equipment among their “wish list”. ISO 14001 and Green Grid were thought to be the leading standards for certifying a Green datacentre.

Companies who have already adopted a Green strategy said that the most important goal of their strategy was in reducing energy costs, but other benefits including climate change, customer image, cost of compliance and updating datacentres were also important. Despite the challenges facing the global economy, 58 percent of respondents had increased their focus on Green initiatives and 69 percent revealed that carbon credits were part of their strategy.

About Digital Realty Trust, Inc.

Digital Realty Trust owns, acquires, redevelops, develops and manages technology-related real estate. The Company is focused on providing Turn-Key Datacentre(SM) and Powered Base Building(SM) datacentre solutions for domestic and international tenants across a variety of industry verticals ranging from information technology and internet enterprises, to manufacturing and financial services. Digital Realty Trust’s 75 properties, excluding one property held as an investment in an unconsolidated joint venture, contain applications and operations critical to the day-to-day operations of technology industry tenants and corporate enterprise datacentre tenants. Comprising approximately 13.0 million square feet (more than 1.2 million metres squared) as of April 30, 2009, including 1.2 million square feet (more than 111,000 metres squared) of space held for redevelopment, Digital Realty Trust’s portfolio is located in 27 markets throughout Europe and North America. For additional information, please visit Digital Realty Trust’s website at www.digitalrealtytrust.com.

Safe Harbor Statement

This press release contains forward-looking statements which are based on current expectations, forecasts and assumptions that involve risks and uncertainties that could cause actual outcomes and results to differ materially, including statements related to potential regulation and the concerns of survey respondents. These risks and uncertainties include the impact of the current deterioration in the global economy, including the turmoil in the financial and credit markets; the downturn of local economic conditions in our geographic markets; decreases in information technology spending, including as a result of economic slowdowns or recession; adverse economic or real estate developments in our industry or the industry sectors that we sell to; decreases in real estate valuations and resulting impairment charges; our dependence upon significant tenants; bankruptcy or insolvency of one or more major tenants or a significant number of smaller tenants; defaults on or non-renewal of leases by tenants; our failure to obtain necessary debt and equity financing for refinancing current debt obligations, undertaking or completing redevelopment, completing acquisitions or other purposes; increased interest rates and operating costs; our failure to repay debt when due or our breach of covenants or other terms contained in our loan documents; financial market fluctuations; changes in foreign currency exchange rates; our ability to manage our growth effectively; difficulty acquiring or operating properties in foreign jurisdictions; our failure to successfully operate acquired or redeveloped properties; risks related to joint venture investments, including as a result of our lack of control of certain of these investments; delays or unexpected costs in development or redevelopment of properties; decreased rental rates or increased vacancy rates; increased competition or available supply of data center space; inability to successfully redevelop and lease new properties and space held for redevelopment; difficulties in identifying properties to acquire and completing acquisitions; our inability to acquire off-market properties; our inability to comply with the rules and regulations applicable to public companies; our failure to maintain our status as a REIT; possible adverse changes to tax laws; restrictions on our ability to engage in certain business activities; environmental uncertainties and risks related to natural disasters; changes in foreign laws and regulations, including those related to environmental matters, taxation and real estate ownership and operation; changes in real estate and zoning laws; and increases in real property tax rates. For a further list and description of such risks and uncertainties, see the reports and other filings by the Company with the United States Securities and Exchange Commission, including the Company’s annual report on Form 10-K for the year ended December 31, 2008 and the Company’s quarterly reports on Form 10-Q for the quarter ended March 31, 2009. The Company disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

For Additional Information: A. William Stein Chief Financial Officer and Chief Investment Officer Digital Realty Trust, Inc. +1-415-738-6500 Pamela A. Matthews Investor/Analyst Information Digital Realty Trust, Inc. +1-415-738-6500 Bernard Geoghegan Senior Vice President International Operations Digital Realty Trust, Inc. +353(1)2450650

Source: Digital Realty Trust

A. William Stein, Chief Financial Officer and Chief Investment Officer, or Pamela A. Matthews, Investor/Analyst Information, both +1-415-738-6500, or Bernard Geoghegan, Senior Vice President, International Operations, +353(1)2450650, all of Digital Realty Trust, Inc.