Never as in recent months, the complex and multiform topic of fragility has imposed itself as a factor impacting in changing and transforming the concept of territories and landscapes. The exhibition described in this book has the great value of discussing issues that are essential components of our projects, in relation with an innovative and non-banal approach, oriented exactly to the comparison - with high scientifc profle - among different positions. The selected format, a collection of posters and panels, helps to immediately convey the spirit and goal of each personal contribution. A sequence of drawn ideas emerges and - precisely in the integration of different individuals, from the young researchers to the Professors with a long-standing experience - it outlines a composite picture of a great perspective, capable of opening questions and visualizing operational strategies. But the quality and identity of this exhibition are also recognizable within its own special occasion. The tenth edition of the OC OPEN CITY International Summer School is an important moment for the Politecnico di Milano AUIC School. Ita a celebration for one of the most signifcant teaching experiences of recent decades: an intensive design workshop that gathered hundreds of students and professors around the most stressed topics of contemporary debate, at the international level. In this horizon, the exhibition is even more meaningful, because it collects and reinterprets the energies and tensions that the OC Summer School has been able to provoke since its beginnings, within the Piacenza Campus of our Politecnico. Teaching and research have met along lines of disciplinary study and have found their natural fulfllment in the territorial fragility. I like to intend the contents of this book not only as a point of arrival, but as a renewed opportunity for design refections that will engage our School in the next decade.