Within the more than ten years since the founding of lehner gunther in 2004 Johanna and Mathias have built up a large network of clients, colleague’s and other experts; a fact that enables them to execute commissions differing widely in topic and scale.


Since 2012 Mathias is a member of the board of Architectura et Amicitia (Architecture and Friendship), A et A ( He oversees the portfolio of communication including the website.AetA exists since 1855 and it is a collegial platform and presents itself through discussions, publications (Forum) and excursions.

BNA – Royal Institute of Dutch Architects

Since 2011 Mathias heads the international programme at the Royal Institute that maintains international networks of clients and partners. The Royal Institute of Dutch Architects stimulates the development of architecture and to support the practice of eh 1300 architectural practices united in this sector association.

University of Applied Sciences Amsterdam

Next to this she is senior lecturer for architecture and urban planning at the department of Architecture at the Amsterdam University of Applied Sciences. There she develops and organizes parts of the curriculum, works with students and gives lectures. Also, she is attached to the lectoraat MI(d)R, multiple intensive and sustainable use of space at the very same University.
With its slogan ‘Creating Tomorrow’ the University of Applied Sciences Amsterdam’s mission is to build on the future of many students and professionals. It is the largest and most reknown education in its kind within the Netherlands.


Mathias is Chair of the Board of Stichting Kunstfort bij Vijfhuizen, part of the UNESCO World Heritage Site Stelling van Amsterdam.


For Buitenwerkplaats located in the polder in the North of Amsterdam he is member of the Board of Advisors.


Since its constitution LEGU has been a member of Wonderland, a network of young European architects.