To stimulate the realization of long-term corporate goals, ARCADIS NV has stock option plans, as well as stock purchase plans. A description of these plans is provided below.

ARCADIS NV 1994 and 1996 Incentive Plan
At the time of the merger with Geraghty & Miller, Inc. in 1993, ARCADIS NV adopted and later expanded in 1994 and 1996 the existing stock option plans.

ARCADIS NV 2001 Long Term Incentive Share Option Plan In the General Meeting of Shareholders of May 2001, the ARCADIS NV 2001 Long Term Incentive Share Option Plan was introduced. Under this plan, a maximum of 2,500,000 options on ARCADIS NV shares will be granted from 2001 to 2006 to key personnel in ARCADIS NV and its subsidiaries. What is distinct about this plan is the fact that the number of options to be used per year can be determined by a number of pre-set performance criteria as formulated by the Supervisory Board of the Company. These criteria are related to the increase in earnings per share in the preceding book year. These options are provisional in nature and become vested after a period of three years provided the participant is still employed by ARCADIS NV or one of its international subsidiaries. Options issued under this plan are valid for a period of ten years, beginning on the date of issuance. Options are usually granted on the day after the Annual General Meeting of Shareholders; the exercise price will match the closing price of ARCADIS NV shares on the Euronext Amsterdam stock exchange on the day on which the options are granted.In 2005, the number of available options under this plan was 250,000. This was based on an increase in net income from operations per share in 2004 of 9.2% (excluding currency effect). On May 13, 2005, and under the conditions of the 2001 plan, a total number of 210,000 options were granted to, and accepted by, 92 employees worldwide against an exercise price of € 17.94. On the same date, the members of the Executive Board were granted 40,000 conditional options, under the conditions of the 2005 plan, against an exercise price of € 17.94.

Click here for an overview of options granted.

Regulation
Participants in the ARCADIS option plans and share purchase programs are obligated to comply with the "Regulation concerning ownership and trading of securities ARCADIS NV," in as much as this regulation applies to them. If applicable, these participants are prohibited from conducting any transactions in ARCADIS NV securities during closed periods. For all participants, it is obvious that if they have access to or possess insider information, any trading in securities is also prohibited.

ARCADIS NV Employee Share Participation Plan
In cooperation with the Lovinklaan Foundation, ARCADIS NV introduced an Employee Share Participation Plan at the end of 2001, enabling employees to purchase ARCADIS NV shares from the Lovinklaan Foundation against a (pre-fixed) discount.

The Employee Share Participation Plan (at this time) is valid in the Netherlands, United States, Belgium, Germany and France. The discount percentages are based on local laws and regulations and differ on a country-to-country basis, varying from 10% (the Netherlands) to 15% (United States and Germany) to 16.67% (Belgium) and 17.5%
(France). The shares used for this plan, as well as the discount in price, are provided by the Lovinklaan Foundation. Therefore, this plan in no way gives rise for the purchase or issuance of shares by ARCADIS NV itself. In 2005, employees purchased 134,444 shares from the Lovinklaan Foundation. The Lovinklaan Foundation is a shareholder in ARCADIS NV and, at December 31, 2005, held a 21.3% stake in the Company's share capital.

Shares and options held by members of the Executive Board and Supervisory Board

Interests held by members of the Executive Board
The interests held in the share capital of ARCADIS NV by those who during 2005 were members of the Executive Board are noted in the table below:

Shares ARCADIS NV	1 January 2005	31 December 2005
Harrie Noy	33,787	34,122
Michiel Jaski	1,436	1,719
Provisional shares ARCADIS NV
Harrie Noy	–	10,000*
Michiel Jaski	–	7,000*
* Amounts based on granting of 100% of the reference amounts

Options Executive Board
Overview of options outstanding to the members of the Executive Board (year-end 2005)

	Option plan from year	Granted  in year	Granted	Exerciseprice	Exercised	Outstanding	Expiration date
Harrie Noy	2001	2001	30,000	€ 9.20	20,000	10,000	05-22-2011
		2002	15,000	€ 10.79	–	15,000	05-15-2012
		2003	17,500	€ 8.93	–	17,500	05-13-2013
	2005	2005	25,000*	€ 17.94	–	25,000	05-10-2015
Michiel Jaski	2001	2001	17,500	€ 9.20	17,500	0	05-22-2011
		2002	10,000	€ 10.79	–	10,000	05-15-2012
		2003	14,000	€ 8.93	–	14,000	05-13-2013
	2005	2005	15,000*	€ 17.94	–	15,000	05-10-2015
*Amounts based on granting of 100% of the reference amounts

Shares and options held by members of the Supervisory Board
The interests held in the share capital of ARCADIS NV by those who during 2005 were members of the Supervisory Board are noted in the table below:

Shares ARCADIS NV	January 1, 2005	December 31, 2005
Ross A. Webber	1,130 shares	1,130 shares

Members of the Supervisory Board hold no ARCADIS options.