If, as Thomas Aquinas once wrote, "in the case of necessity all things are common", we need to read this book this same week. Cesar Rendueles - a sociologist whose new books are always an event for those of us interested in the most pressing issues of our lives - does not simply explain why we are in a condition of "necessity," that is, framed in ecological, political, and technological emergencies, but also how to reclaim our "commons." These are collaborative social institutions that regulate resources (public goods and services) which in a relatively brief period of time will become less and less accessible for millions of people that currently take them for granted. This book provides all those brave social forces advocating for democratic, progressive, and emancipatory strategies a global "politics of commons" that seems to be our last chance as we enter the new regime of postcapitalism. Aquinas himself would have endorsed Rendueles’ new book. Santiago Zabala, ICREA Research Professor, Pompeu Fabra University, Spain