Friedrich Stowasser (1928, Vienna - 2000, New Zealand), better known by the name of Friedrich Hundertwasser, was a painter, thinker, and architect, or rather an “architecture doctor,” as he declared in his manifesto of January 24, 1990. With his tremendous love of nature, he is one of the pioneers of humanist and environmentalist architecture, which attempted to reconcile creativity and ecology. His creations are organic and full of imagination. Yet, Hundertwasser was more radical in his philosophy. As expressed in his remarkable eco-artistic manifestos, and works of art (paintings, posters, stamps and flags), his message remains profoundly and viscerally ecological. His pictorial work, characterised by an organic abundance of forms and by the brilliance of its colours remains unique and full of hope. Reuniting for the first time the analysis of Hundertwasser’s work by Pierre Restany with numerous texts written by Hundertwasser himself, this books offers a global vision of the work and art of this prolific artist.