Digital Realty Trust Adds London Property to ISO Certified Properties

Official Recognition of Information Security and Quality Management Systems with ISO 27001 and ISO 9001 Accreditation

LONDON, January 25, 2011 - Information security and quality management systems are fundamental
considerations for corporate enterprises, particularly when it comes to the
delivery of critical business applications. In order to best serve its
customers, Digital Realty Trust, Inc. (NYSE: DLR), a leading global wholesale
data centre provider, is committed to achieving the highest standards of
practice in all markets where it provides customers with flexible, reliable
and secure datacentre facilities.

For its Redhill Turn-Key Datacentre(R) in London, Digital Realty Trust
has been accredited by the International Organization for Standardization
(ISO) with ISO 27001 and ISO 9001 certifications. The ISO 27001 and 9001
standards are industry-leading accreditations for best practice in
information security and quality management systems. These accreditations are
in addition to ISO 27001 and ISO 9001 certifications for Digital Realty
Trust's European Operations as well as its Dublin and Paris properties. These
accreditations, which cover personnel, contractors, corporate information,
the provision of data centre infrastructure, power, cooling and physical
security, represent Digital Realty Trust's commitment to its customers.

"Information security and quality management systems are top priorities
for businesses, and the processes required to safeguard data are constantly
evolving," said Frederick S. Potter, Managing Director International for
Digital Realty Trust. "Achieving these ISO certifications reflects our
commitment to providing Digital Realty Trust customers with industry best
practices by adopting and driving forward both information security and
quality management systems."

The ISO 27001 Information Security Management System identifies Digital
Realty Trust as exhibiting good corporate governance and having a clear
framework for legal compliance. The standard ultimately certifies that
Digital Realty Trust's Information Security Management system safeguards
confidential customer information, and that it provides a basis for sharing
information with other organisations in a secure manner.

The ISO 9001 Quality Management System is an internationally recognised
standard for quality management. It provides a framework of globally
acknowledged principles that Digital Realty Trust draws upon to ensure client
satisfaction. The ISO 9001 standard also represents an accreditation for the
quality of Digital Realty Trust's staff. In earning certification, the
Company continues its commitment to delivering the highest standards of
service to its customers.

About Digital Realty Trust, Inc.

Digital Realty Trust, Inc. enables customers to deliver critical business
applications by providing secure, reliable and cost effective datacentre
facilities. Digital Realty Trust's customers include domestic and
international companies across multiple industry verticals ranging from
information technology and Internet enterprises, to manufacturing and
financial services. Digital Realty Trust's 96 properties, excluding two
properties held as investments in unconsolidated joint ventures, comprise
approximately 16.8 million square feet as of December 9, 2010, including 2.3
million square feet of space held for redevelopment. Digital Realty Trust's
portfolio is located in 28 markets throughout Europe, North America and
Singapore. For additional information, please visit Digital Realty Trust's
website at www.digitalrealtytrust.co.uk.

Safe Harbour Statement

This press release contains forward-looking statements which are based on
Digital Realty Trust, Inc.'s current expectations, forecasts and assumptions
that involve risks and uncertainties that could cause actual outcomes and
results to differ materially, including statements related to its practices
and its ISO accreditation. These risks and uncertainties include, among
others, the following: the impact of the recent deterioration in global
economic, credit and market conditions; current local economic conditions in
its geographic markets; decreases in information technology spending,
including as a result of economic slowdowns or recession; adverse economic or
real estate developments in its industry or the industry sectors that it
sells to (including risks relating to decreasing real estate valuations and
impairment charges); its dependence upon significant tenants; bankruptcy or
insolvency of a major tenant or a significant number of smaller tenants;
defaults on or non-renewal of leases by tenants; its failure to obtain
necessary debt and equity financing; increased interest rates and operating
costs; its failure to repay debt when due or its breach of covenants or other
terms contained in its loan facilities and agreements; financial market
fluctuations; changes in foreign currency exchange rates; its inability to
manage its growth effectively; difficulty acquiring or operating properties
in foreign jurisdictions; its failure to successfully operate acquired or
redeveloped properties; risks related to joint venture investments, including
as a result of its lack of control of such 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
centre space; its inability to successfully develop and lease new properties
and space held for redevelopment; difficulties in identifying properties to
acquire and completing acquisitions; its inability to acquire off-market
properties; its inability to comply with the rules and regulations applicable
to reporting companies; its failure to maintain its status as a REIT;
possible adverse changes to tax laws; restrictions on its 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 taxation and real estate ownership and operation; and
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 Digital Realty Trust, Inc. with the U.S.
Securities and Exchange Commission, including Digital Realty Trust, Inc.'s
Annual Report on Form 10-K for the year ended December 31, 2009 and Digital
Realty Trust, Inc.'s Quarterly Reports on Form 10-Q for the quarters ended
March 31, 2010, June 30, 2010 and September 30, 2010. Digital Realty Trust,
Inc. 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      Pamela A. Matthews      Frederick S. Potter
    Chief Financial       Investor/Analyst        Head of International
    Officer and Chief     Information             Operations
    Investment Officer
    Digital Realty        Digital Realty          Digital Realty
    Trust, Inc.           Trust, Inc.             Trust, Inc.
    +1-415-738-6500       +1-415-738-6500         +44-207-954-9100

A. William Stein, Chief Financial Officer and Chief Investment Officer, +1-415-738-6500, or Pamela A. Matthews, Investor/Analyst Information, +1-415-738-6500, or Frederick S. Potter, Head of International Operations, +44-207-954-9100, all of Digital Realty Trust, Inc.