Co-option is a form of appointment whereby new members are appointed by existing members of a group/board. In the Netherlands co-option primarily occurs in foundations. The appointment of new board members of a foundation is done by the existing board members. Basically the board maintains itself through co-option. While this is not a statutory requirement, co-option is provided in most articles of association A document, drawn up when a Dutch company or legal person is set up, and which regulates the operations of the company and defines its purpose.
» Meer over articles of association Articles of Association of foundations.

Appointment through co-option differs from other appointment procedures for Dutch legal persons. Usually a member of the (supervisory) board is appointed by a different body of that legal person (such as the shareholders’ meeting).

Co-option is also a frequently used method of appointment for informal associations such as a residential group (e.g. student house).