IG BAU and ACS Agree on Future Cooperation for HOCHTIEF

FRANKFURT and MADRID, December 22, 2010 - This announcement and the information contained herein are restricted and
are not for release, publication or distribution, in whole or in part, in or
into the United States or Japan.

German construction workers union IG BAU and ACS have agreed on key
issues of cooperation once ACS has achieved the majority of HOCHTIEF.
Yesterday, both parties signed a respective agreement in Madrid:

"Commitments of ACS, Actividades de Construcción y Servicios,
S.A. (ACS) towards Industriegewerkschaft Bauen-Agrar-Umwelt (IG BAU) in
connection with the announced ACS tender offer for shares of HOCHTIEF AG

The following document sets out the key terms of commitments (Abreden)
which ACS is willing to make towards IG BAU. These commitments will become
effective as soon as ACS gains a majority shareholding in HOCHTIEF AG. ACS
will act in the spirit of these commitments already once its present tender
offer to the shareholders of HOCHTIEF has been successfully settled and ACS
has attained a shareholding of more than 30%. The commitments will expire on
31 December 2013. The parties will agree on any extensions of or amendments
to these commitments well in advance of their expiry.

ACS will sign a code of ethics which will be based on the "Model
International Framework Agreement" of the Building and Wood Workers'
International (BWI).

Without prejudice to the mandatory and exclusive right of the management
board to manage the company under the German Stock Corporation Act, ACS, as
the majority shareholder of HOCHTIEF AG, commits itself to and will support
the following, provided that there is no material adverse change affecting
HOCHTIEF:

    1 HOCHTIEF AG will remain an independent and co-determined directly or
      through subsidiaries operational company. Any reorganization into an
      entity governed by European law (e.g.: SE) is excluded.

    2 The HOCHTIEF AG headquarters will remain in Essen.

    3 The management board of HOCHTIEF AG will be in control of the company's
      operational business. ACS does not pursue a domination agreement and
      won't interfere as a shareholder in operational management decisions.

    4 ACS respects the collective and works-council agreements of HOCHTIEF
      and has no intention to bring about changes to the working conditions
      of the employees nor to the co-determination in works councils and in
      the supervisory board.

    5 ACS will not exert its influence to the effect that the number of
      employees currently employed in the HOCHTIEF group under German law is
      reduced through employer termination notices for commercial reasons
      (betriebsbedingte Kündigungen) during the term of these commitments.
      ACS would support the management board of HOCHTIEF if it decided not
      to use employer termination notices for commercial reasons.

    6 ACS will support a strategy of HOCHTIEF aiming for sustainable and
      adequate profitability developing national markets - in particular the
      German market - not only to secure employment but also for creating
      additional jobs.

    7 Co-operation across all businesses of the HOCHTIEF group should be
      increased. Going forward, the strategy of the business units is to
      focus, to a greater extent, on generating orders for the respective
      other business units of the group.

    8 IG BAU is and will remain the only German labour union within the
      HOCHTIEF group for all employments under German law.

    9 The worker directors in the co-determined companies of the HOCHTIEF
      group shall only be proposed in consultation with (im Benehmen mit)
      the union representatives on the respective supervisory board.

Having obtained the above mentioned commitments from ACS, IG BAU is
convinced that this now allows for a constructive relationship between
HOCHTIEF, its employees and ACS."

ACS welcomes the agreement with IG BAU as a solid basis for a
constructive cooperation going forward.

More information about the public tender offer is available at
www.acs-offer.com.

About Grupo ACS

Grupo ACS (ACS, Actividades de Construcción y Servicios, S.A.),
headquartered in Madrid/Spain, is a world leader in infrastructure
development. In 2009, the Group's revenues totaled EUR15,606 million. ACS
has more than 146,000 employees operating in 41 countries. ACS is listed
on the Madrid Stock Exchange.

Important Notice:

This announcement is neither an offer to purchase nor a solicitation of
an offer to sell shares in HOCHTIEF Aktiengesellschaft (the "HOCHTIEF
Shares"). Moreover, the announcement is neither an offer to purchase nor a
solicitation to purchase shares in ACS, Actividades de Construcción y
Servicios, S.A. (the "ACS Shares"). The public offer by ACS, Actividades de
Construcción y Servicios, S.A. to the shareholders of HOCHTIEF
Aktiengesellschaft is exclusively made on the basis of the terms set out in
the offer document. Investors and holders of HOCHTIEF Shares are strongly
recommended to read the offer document and all announcements published in
connection with the public offer, since they contain important information.

Subject to certain exceptions, the public offer will not be made directly
or indirectly, in or into the United States, Japan or any other jurisdiction
where to do so would constitute a violation of the laws of such jurisdiction,
or by use of the mails or by any means or instrumentality (including without
limitation, facsimile transmission, telephone and the internet) of interstate
or foreign commerce, or any facility of a national securities exchange, of
the United States, Japan, or any other jurisdiction where to do so would
constitute a violation of the laws of such jurisdiction. Accordingly, copies
of this announcement or any accompanying documents are not being, directly or
indirectly, mailed or otherwise distributed, forwarded or transmitted in,
into or from the United States, Japan, or any other jurisdiction where to do
so would constitute a violation of the laws of such jurisdiction.

The ACS Shares have not been, and will not be, registered under the US
Securities Act of 1933 or with any securities regulatory authority of any
state or other jurisdiction of the United States or under the applicable
securities laws of Japan. Accordingly, subject to certain exceptions, the ACS
Shares may not be offered or sold within the United States or Japan or any
other jurisdiction where to do so would constitute a violation of the laws of
such jurisdiction, or to or for the account or benefit of any person in the
United States or Japan.

To the extent permissible under applicable law or regulation, ACS and
persons acting on its behalf may from time to time make certain purchases of,
or arrangements to purchase, directly or indirectly, HOCHTIEF Shares or any
securities that are immediately convertible into, exchangeable for, or
exercisable for, HOCHTIEF Shares, other than pursuant to the public offer,
before, during or after the period in which the offer remains open for
acceptance. These purchases may occur either in the open market at prevailing
prices or in private transactions at negotiated prices. Any information about
such purchases and arrangements to purchase will be disclosed as required by
law or regulation in Germany or other relevant jurisdictions.

This announcement includes forward-looking statements about ACS, HOCHTIEF
and the enlarged group. By their nature, forward-looking statements involve
risks and uncertainties because they relate to events and depend on
circumstances that may or may not occur in the future. ACS cautions you that
forward-looking statements are not guarantees of the occurrence of such
future events or of future performance and that in particular the actual
results of operations, financial condition and liquidity, and the development
of the industry in which ACS and HOCHTIEF operate may differ materially from
those made in or suggested by the forward-looking statements contained in
this announcement. Any forward-looking statements speak only as at the date
of this announcement. Except as required by applicable law, ACS does not
undertake any obligation to update or revise publicly any forward-looking
statement, whether as a result of new information, future events or
otherwise.

    Company Contacts:

    German and international media:
    Phoebe Kebbel
    Hering Schuppener Consulting
    Phone:  +49-69-921874-77
    Mobile: +49-173-2862110
    pkebbel@heringschuppener.com

    Investor Relations:
    Grupo ACS
    Avda. Pío XII, no 102
    28036 Madrid, Spain
    Tel: +34-91-343-92-00
    Fax: +34-91-343-94-56
    e-mail: infogrupoacs@grupoacs.com

Company Contacts: German and international media: Phoebe Kebbel, Hering Schuppener Consulting, Phone: +49-69-921874-77, Mobile: +49-173-2862110, pkebbel at heringschuppener.com; Investor Relations: Grupo ACS, Avda. Pío XII, no 102, 28036 Madrid, Spain, Tel: +34-91-343-92-00, Fax: +34-91-343-94-56, e-mail: infogrupoacs at grupoacs.com