In this paper, we analyze an unrecognized actor of the creative cities: creative collectives. We identify three active layers in the creative cities. Firms – the upperground – absorb knowledge emerging from the creative activities in the city whereas actors from the underground explore and suggest new creative ways. In this context, creative collectives from the middleground play a role of knowledge integration and transfer between the underground and the upperground. Through some empirical examples, we assess the nature and roles of those collectives, and discuss the various relationships they could develop with firms and their milieu.