Under CopyrightBodenheimer, MiriamMiriamBodenheimerDütschke, ElisabethElisabethDütschke2022-05-232022-05-232021https://publica.fraunhofer.de/handle/publica/417927https://doi.org/10.24406/publica-7310.24406/publica-73The aim of this paper is to disentangle agency, activities and actor roles and to link them with the phases of a transition over time. We define agency in this con-text as the capability that arises from the combination of individual interests and resources. Activities are understood as agency put into practice, while roles are characterized as a set of recognizable activities by an actor. For the development of transitions over time and through different stages the paper builds on the five prototypical phases as described in the Dialectic Issue Lifecycle Model: (1) prob-lem emergence and regime neglect; (2) rising public concerns and defensive re-gime responses; (3) political debate/controversies and defensive hedging; (4) for-mation and implementation of substantive policy and industry diversification; (5) stabilization of the new regime and strategic reorientation. Using these defini-tions and this dynamic conception of transitions as a foundation, we are able to conceptualize (1) how different roles influence the progress of a transition (2) how roles and their relevance change dynamically over the course of the transi-tion and (3) how a variety of actors can take on certain roles in transition pro-cesses. The paper outlines the critical activities for each phase and their impact on the transition process, i.e. how those activities either move the transition for-ward or hinder its progression. We link these activities with actor roles and role constellations. Our dynamic concept provides researchers with a conceptual foun-dation to empirically identify different roles, activities, and their impact on a tran-sition process. Thereby it gives a framework to an actor centered research ap-proach. It further allows for tailoring of policy measures more specifically to the current status of a transition as well as identifying the state of progress of an on-going transition based on the current activities.enRolesActorsSocio-technical TransitionsTransition Dynamicspresentation