In the face of climate, environmental, energy and societal changes, our fields of intervention, construction and regional development are undergoing major upheavals and are likely to experience even greater ones. Time is running out. This is why we have taken the initiative of the Manifesto for a Happy Frugality attached, written jointly by Dominique Gauzin-Müller (architect), Alain Bornarel (engineer) and Philippe Madec (architect and urban planner). This manifesto opens the paths of frugality, alternatives to visions that are technocratic, high-intensity, wasteful of energy and resources of all kinds. If the initiative interests you and if you would like to participate in this movement collectively, please don’t hesitate to sign and forward it to your networks.