How does a crisis come into being, exist and pass? In response to these classical questions of the social sciences, this issue of Tracés takes a step aside by examining "states of crisis", i.e., the scholarly and ordinary procedures by which a given situation, in different social worlds, is qualified as "critical" and objectified as a crisis.

This issue, initiated just a few months after the French government's announcement of new restrictive measures (April 2021), proposes to examine the destabilization and redevelopment caused by the pandemic is in the retail sector, and to study its temporary or lasting consequences on urban space.

This special issue of the journal Tracés focuses on interdisciplinary practices across the social sciences and natural sciences. we sought to reflect on ways of practising interdisciplinarity across disciplines whose research objects, methods, epistemologies and theoretical references seem to differ significantly