Filippo Celata and Filip Stabrowski edited a Special feature for the journal City, on “Crowds, communities, (post)capitalism and the sharing economy”. The aim is to reflect upon the ambivalences of the sharing economy as a discourse and as a practice, and upon the disillusionment about its potential to create a space for postcapitalist, peer-to-peer, non-market or more socially intense forms of exchange. At the same time, these ambivalences show how the diffusion of sharing practices is open to a variety of different outcomes, and an interesting terrain for exploring the limits and alternatives to digital capitalism as we know it. On this basis, the special feature includes an introductory article by the editors, aimed at providing a critical review of research about the sharing economy, and at introducing the following articles, which focus in particular on the role that ‘communities’ and ‘crowds’ play in the discursive formation and in the practical operations of digital sharing platforms.