Constant Catalogue Raisonné

One of the main goals of Fondation Constant is to realise a website offering access to the full body of work created by Constant during his lifetime, a so called digital catalogue raisonné. To set up the database for this, Fondation Constant is in the process of gathering all data regarding Constant’s works of art and their whereabouts.
NB: This website strives to become the catalogue raisonné of Constant's oeuvre BUT is a work-in-progress! We add works, publications, exhibitions and related information to the website on a daily basis.

Besides financial support there is another way in which you can help the foundation to realise the catalogue raisonné. If you are in possession of (a) work(s) of art by Constant (1920-2005) you can alert us by filling in the catalogue raisonné form here:


Choose the option oral assessment at the start of the form.
Pleas note that general terms and conditions apply.

Criteria for including a work in the Constant Catalogue Raisonné
1. The work appears in Constant’s archives:
- As an archive entry
- As an ektachrome
- As a photo

2. The work appears in valid documentation:
- The work appears in books published by Constant himself.
- The work appears in catalogues of exhibitions, set up with Constant’s knowledge and/or co-operation.
- The work appears on invitations to exhibitions, set up with Constant’s knowledge and/or co-operation.
- The work appears on sales and/or price lists and invoices in Constant archive.

3. The provenance of the work is legit:
- The work has a documented and reliable history leading back to Constant.

When the work of art is known to the foundation and no doubt exists about its authenticity will be added to the catalogue raisonné.

The writing of the catalogue raisonné is supported by the Academic Committee, which advises Mrs. Nieuwenhuys on best practices, content, quality measures, procedures and format.

The Academic Committee consists of:
Dr. Marcel Hummelink | Chair of the Academic Committee: author of the thesis, self-published, Apres nous la liberté. Constant and the artistic Avant-garde in the years 1946-1960. He teaches social studies at Stedelijk Gymnasium Haarlem.
Prof. dr. Katja Kwastek: Professor of Art History of the Modern Age at the Faculty of Arts of the VU Amsterdam
Drs. Julia Mullié: independent researcher and PhD Candidate at the Amsterdam School for Cultural Analysis. She currently works on an extensive research on the oeuvre of stanley brouwn.

Till 2023
drs. Els Hoek: Author of the catalogue raisonné of Theo van Doesburg and curator at Museum Boijmans van Beuningen

*For the high quality photograph's the foundation works with Tom Haartsen Fotografie: +31 (0)20 496 35 23

Fondation Constant is a not for profit organisation and your donations are always welcome and ever necessary:


Fondation Constant


Marcel Hummelink
Marcel Hummelink


Katja Kwastek
Katja Kwastek


Julia Mullié, photo by Julian Mollema
Julia Mullié, photo by Julian Mollema