Sustainability needs rigor: this was the premise of the World SB14 congress held in Barcelona on 28, 29, and 30 October. Organized by Green Building Council España, the event brought together a good number of national and international institutions besides leading experts on the subject, which was deliberated on in open sessions presenting a wide repertoire of themes, from traditional architecture to global governance, along the way touching on the study of the life cycle, management of resources, and the new business models arising from sustainable administration. The results have been summarized in a manifesto, ‘Building a Common Home,’ accessible at the congress website (www.wsb14barcelona.org)