1. Results Third Quarter 2006 Harrie Noy, CEO Analyst Conference Call, November 15, 2006 Infrastructure, environment, facilities

2. Excellent third quarter 2006 Gross revenue 32% higher, strong organic growth at 12% Net income from operations 63% higher Strong results across the board, geographic and per service area Expected increase net income from operations raised to 40 to 45% Margin considerably higher at 9.6% compared to 8.0% last year Target margin increased to 10% (was 8%) ARCADIS is now operating higher in the value chain

3. Gross revenue Ebita Ebita recurring Net income Net income per share 2) Net income from operations 1) Ditto per share 1,2) 1) Before amortization and non-operational items 2) In 2006 based on 20.2 million shares outstanding (2005: 20.2 million) 2006 311 19.6 10.7 0.53 12.3 0.61 2005 236 13.1 6.3 0.31 7.5 0.37 _  _ 32% 50% 70% 63% Income third quarter 2006: € 12.3 million

4. Gross revenue Ebita Ebita recurring Net income Net income per share 2) Net income from operations 1) Ditto per share 1,2) 1) Before amortization and non-operational items 2) In 2006 based on 20.2 million shares outstanding (2005: 20.2 million) 2006 892 54.9 30.3 1.50 33.5 1.65 2005 692 38.5 36.4 20.8 1.03 20.8 1.02 _  _ 29% 43% 51% 46% 61% Income first nine months 2006: € 33.5 million

5. Main developments Figures refer to first nine months 2006 Strong organic growth in the Netherlands: >10% –Considerable contribution from facility management contract DSM/Sabic –Significant investment in rail infrastructure renewal/maintenance –More PPP initiatives; outsourcing by Ministry Public Works –Strong demand for project management and cost consultancy Continued growth in the U.S. and Brazil – Organically in U.S. 12%; in Brazil >20% Strong contributions from recent acquisitions – Especially BBL (U.S.) and AYH (U.K.) After delays, start up of major infrastructure projects in Poland Integration of BBL is progressing well

6. Currency -3% +1% 5% 1% -1% 2% Selling prices +1% -0% 0% 0% 0% 0% Growth accelerates 33%

7. Considerable growth of Ebita First nine months 51% on recurring basis In € million 35% 2% 14% 38.5 54.9 36.4 Organic increase mainly from U.S., Brazil and Netherlands

8. Acquisitions to strengthen portfolio Acquisitions 2006 Environment NL Water Germany Management services UK Environment Belgium Walloon Belgium Management services US Total In Situ Technieken Dresdner Grundwasser Berkeley Consulting Ecolas BCT PinnacleOne Staff 10 20 100 60 65 230 485 GR in € 1.5 10 6 28 53 Cons. from 1.4.06 1.7.06 1.8.06 1.10.06 1.11.06

9. The service areas Infrastructure Environment Facilities

10. Strong organic growth in all service areas Figures relate to first nine months 2006; (..) = organic growth

11. Organic growth strong at 8% In Q3 accelerated growth in Netherlands and U.S. Higher investment levels in Dutch market: rail, PPP, highways U.S.: decline land development compensated by transportation and water markets Continued growth in Brazil: mining and energy Infrastructure +5% (+8%) Rail renewal market strong

12. Overall revenue growth mainly coming from acquisitions (BBL) Main contribution to organic growth of 8% from U.S. (GRiP®) Softening in Q3 due to Poland and less subcontracting in U.S. Good synergy from BBL & Greystone, inside + outside U.S. U.K. and Netherlands strongest growth in Europe Environment +77% (+8%) GRiP® continues growth

13. ARCADIS Worldwide Project Consulting launched Facility management DSM/Sabic drives organic increase Organic growth net revenue at 8% Acquisition AYH strong growth contributor Good demand for project management in NL, U.K. and Germany Higher activity level in Belgium and France Facilities +29% (+17%)

14. New Margin Targets

15. Target margin was exceeded in 2005: 8.2% In 2000 margin target set at 8% Strong margin improvement 2000-2005 From 6.0% to 8.2%, almost 40% Portfolio changes & focus added value: structurally higher margin So: evaluation of margins Internal and external benchmarking Improved consistency of margin calculation Margin definition is unchanged (Ebita as a % of net revenue)

16. New margin target for ARCADIS set at 10% Targets per service area Adjusted Margin target margin 2005 Infrastructure 7.1% 8% - 9% Environment11.0% 12% - 13% Facilities 7.0% 10% - 11% Total 8.2% 10% When portfolio changes, margins to be reviewed again Focus remains on productivity improvements and higher value added Reaching targets also depends on market conditions

17. Outlook

18. Outlook per service area Infrastructure Economic growth creates room for project funding More PPP initiatives attract private sector investment Demand for flood protection work is increasing Environment Growing interest in environment and sustainability Synergy with BBL offers opportunities with multinationals GRiP® continues to drive growth Facilities Economic growth drives project management demand Facility management benefits from outsourcing trend AWwPC launched for international real estate investors

19. Outlook for full year 2006 improved ARCADIS is well positioned in markets that offer opportunity Synergy contributes to growth Integration BBL brought to conclusion in coming months Integration BBL and SOX 404: approx. € 5 million out of pocket costs Acquisition policy continued Expected increase net income from operations raised to 40% to 45% (barring unforeseen circumstances) ARCADIS is well on track

20. Thank you