This paper is concerned with the way technological expectations are generated, articulated and deployed in processes of large-scale socio-technical change. We argue that expectations are intrinsic to all social action, so that visions of the future are both ubiquitous and context-specific. Agents will act in relation to private visions of the future that are complexly related to shared or collective visions. Characteristic features and forms of visions as they relate to socio-technical regimes are identified, and the specific roles visions play in the context of actor networks engaged in processes of systems innovation are discussed. Visions are seen as 'bids' that are deployed by actors in processes of coalition-formation and coordination. Examples from a range of visions of more sustainable systems are used to illustrate the main arguments. The paper ends by discussing the normative features of socio-technical expectations. © 2006 Taylor & Francis.