Exhibit 99.1

              Citrix Completes Acquisition of XenSource

    LAS VEGAS--(BUSINESS WIRE)--Oct. 22, 2007--Today at Citrix
iForum(TM), the world's largest application delivery conference and
expo, Citrix Systems, Inc. (Nasdaq: CTXS) announced it has completed
the acquisition of XenSource, Inc., a privately held leader in
enterprise-grade virtual infrastructure solutions. The purchase price
for the transaction was approximately $500 million payable in a
combination of cash and Citrix common stock.

    This acquisition moves Citrix, a pioneer in the application
virtualization market, into adjacent server and desktop virtualization
markets -- expected by Citrix to grow to nearly $5 billion over the
next four years. By acquiring XenSource, Citrix is now the only
company to offer organizations an end-to-end application delivery
infrastructure that leverages the method of application, desktop and
server virtualization best suited for the dynamic delivery of
applications to any user (see today's separate press release on the
company's enhanced virtualization strategy).

    As previously announced on Aug. 15 upon close of the acquisition
the XenSource team and products will form the core of the new
Virtualization & Management Division of Citrix dedicated to building
and growing these important new businesses. Peter Levine, XenSource,
CEO, will lead the new division, reporting directly to Mark Templeton,
Citrix president and CEO. Under Peter's leadership, this new division
will oversee Citrix's businesses in server virtualization and
application delivery management solutions as part of the company's
overall application delivery infrastructure strategy.

    Citrix also reiterated its commitment to maintaining and growing
support for the independent Xen open source community which develops
the underlying virtualization engine used by many commercial products
throughout the industry, including those from XenSource. The Xen
project, which includes significant contributions from companies like
Intel, AMD, HP, IBM and Dell, is led by XenSource co-founder, and new
Citrix employee, Ian Pratt. Since news of the acquisition, XenSource
has worked with the key contributors to the Xen project to develop
procedures for independent oversight of the project, ensuring that it
continues to operate with full transparency, fairness and vendor
neutrality. Citrix agrees these principles are critical to the
continued role of Xen as a freely available open source industry
standard for virtualization.

    "The XenSource products, team and culture are a great addition to
the Citrix family," said Mark Templeton, president and chief executive
officer for Citrix. "The combination of Citrix and XenSource brings
together application, desktop and server virtualization to deliver
more innovation, choice and flexibility to the market, including our
installed base of more than 200,000 customers worldwide. As
application delivery becomes a top issue for IT and the world becomes
more dynamic, we find it important to be sure we are providing
customers the most cutting-edge technologies out there."

    About iForum 07 - The App Delivery Expo

    Now in its tenth year, the Citrix App Delivery Expo is the
industry's largest conference focused entirely on application delivery
infrastructure, bringing together thousands of business leaders, IT
managers and technology leaders from around the world. Application
delivery infrastructure best practices will be highlighted in more
than 60 sessions, including keynotes and general sessions from
analysts at Gartner, Forrester, IDC and Yankee Group, as well as
industry leaders like Accenture, Dell, Microsoft, HP, IBM, Intel,
Oracle and SAP. The conference also features 15 enterprise customer
presentations, vendor exhibits, technology labs, hands-on technical
workshops, panel discussions, and product demonstrations. The event
will present thought leaders and cutting-edge technology behind some
of the hottest trends in the market, including virtualization, desktop
delivery and application networking. Held at the Mandalay Bay Resort
and Casino in Las Vegas, NV, from October 22-25, 2007, the Citrix App
Delivery Expo will also feature keynotes by Citrix executives
including Mark Templeton, president and CEO. More information is
available at http://www.citrixiforum.com.

    About Citrix

    Citrix Systems, Inc. (Nasdaq:CTXS) is the global leader and the
most trusted name in application delivery infrastructure. More than
200,000 organizations worldwide rely on Citrix to deliver any
application to users anywhere with the best performance, highest
security and lowest cost. Citrix customers include 100% of the Fortune
100 companies and 99% of the Fortune Global 500, as well as hundreds
of thousands of small businesses and prosumers. Citrix has
approximately 6,200 channel and alliance partners in more than 100
countries. Annual revenue in 2006 was $1.1 billion.

    For Citrix Investors

    This release contains forward-looking statements which are made
pursuant to the safe harbor provisions of Section 27A of the
Securities Act of 1933 and Section 21E of the Securities Exchange Act
of 1934. These forward-looking statements, including statements
regarding the integration of XenSource and its products with Citrix,
XenSource products and Citrix's strategies and future plans do not
constitute guarantees of future performance. Those statements involve
a number of factors that could cause actual results to differ
materially, including risks associated with products, their
development, integration and distribution, product demand and
pipeline, customer acceptance of new products, economic and
competitive factors, Citrix's key strategic relationships, acquisition
and related integration risks as well as other risks detailed in
Citrix's filings with the Securities and Exchange Commission. Citrix
assumes no obligation to update any forward-looking information
contained in this press release or with respect to the announcements
described herein.

    Citrix(R) and Citrix iForum(TM) are trademarks of Citrix Systems,
Inc. and/or one or more of its subsidiaries, and may be registered in
the U.S. Patent and Trademark Office and in other countries. All other
trademarks and registered trademarks are property of their respective
owners.

    CONTACT: Citrix Systems, Inc.
             Julie Geer, 408-790-8543
             julie.geer@citrix.com
             or
             A&R Edelman
             Justine Troy, 917-204-4843
             jtroy@ar-edelman.com