AMSTERDAM, The Netherlands, July 10 -- ARCADIS (EURONEXT: ARCAD), the
international consultancy, design, engineering and management services company,
has finalized the previously announced merger with Malcolm Pirnie, the White
Plains, New York based company active in water and environmental consulting and
engineering. All internal shareholders, representing 100% of the share capital
of Malcolm Pirnie, voted in favor of the merger, showing that this major step is
fully supported by management and senior staff of the company. Malcolm Pirnie,
now a wholly-owned subsidiary of ARCADIS U.S., has more than 1,700 employees
with 2008 gross revenues of $392 million (EUR280 million). The financial terms
of the transaction were disclosed on June 25, 2009 and can be found on the
investors and press section of ARCADIS’ website at
http://www.arcadis-global.com.

Commenting on the merger, ARCADIS CEO Harrie Noy said: I am very pleased with
the acceptance of our merger offer by all of the Malcolm Pirnie shareholders.
This step makes us a major player in the highly attractive global water market
and strongly enhances our position in infrastructure and environment, while
providing a better balance in our public and private sector client mix in the
U.S. In addition, we expect significant business and operational synergies. I
wholeheartedly welcome the Malcolm Pirnie people to ARCADIS and feel excited
about the increased opportunities created by our combined future.

William P. Dee, President CEO of Malcolm Pirnie added: The broad support among
our shareholders and staff signifies the strategic relevance of this bold step.
By joining ARCADIS we create a world leader in water-related consulting and
engineering services, with a global platform that allows us to expand our
services internationally. Broadening our services and geography fits very well
with our philosophy of ’clients first’ and greatly enhances
opportunities for our staff. We look forward to working with the people of
ARCADIS to create solutions for life, here - and throughout the world.

About ARCADIS

ARCADIS is an international company providing consultancy, design, engineering
and management services in infrastructure, environment and buildings, to enhance
mobility, sustainability and quality of life. ARCADIS develops, designs,
implements, maintains and operates projects for companies and governments. With
more than 13,500 employees and over EUR 1.7 billion in gross revenues, the
company has an extensive international network that is supported by strong local
market positions. Visit us on the internet: http://www.arcadis-global.com

About Malcolm Pirnie

Malcolm Pirnie Inc, is a century -old environmental consulting firm, provides
governmental and industrial clients with comprehensive services in water and
wastewater engineering, solid and hazardous waste management, environmental
sciences and, through its Red Oak Consulting Division, a wide range of
management and IT consulting services. With a diversified staff of over 1700
engineers, scientists and consultants in 60+ offices, Pirnie has won over 200
professional awards for project excellence. For more information visit
http://www.pirnie.com.

PRN NLD

SOURCE: ARCADIS NV

For more information please contact: Joost Slooten of ARCADIS at +31-26-3778604
or outside office hours at +31-6-27061880, or e-mail at j.slooten@arcadis.nl.