Contents lists available at ScienceDirect Research Policy journal homepage: www.elsevier.com/locate/respol Six policy intervention points for sustainability transitions: A conceptual framework and a systematic literature review Laur Kanger a,b, ⁎ , Benjamin K. Sovacool a , Martin Noorkõiv b a Science Policy Research Unit, University of Sussex, Jubilee building, BN1 9SL, Falmer, United Kingdom b Institute of Social Studies, University of Tartu, Lossi 36, 51003, Tartu, Estonia ARTICLE INFO Keywords: Sustainability transitions Policy mixes Policy intervention points Transition pathways JEL classification codes: O31 O33 O38 ABSTRACT Recent literature has turned considerable attention to the role of policy mixes in shaping socio-technical systems towards sustainability. However, the identification of relevant policy intervention points has remained a rela- tively neglected topic. This is a potentially significant oversight given that such intervention points constitute a mid-step between means (particular policy instruments) and overall goals (change in the directionality of socio- technical systems). By complementing existing work on policy mixes with additional insights from transitions literature, this paper formulates a conceptual framework of six policy intervention points for transformative systems change. The coding scheme developed on the basis of this framework is used to review current literature on policy mixes in sustainability transitions. It is shown that the latter has so far primarily focused on niche- regime dynamics while largely neglecting the broader context of these interactions. We argue that adopting a wider perspective on intervention points can aid future work on policy mixes by enabling the identification of root causes and critical problems of ongoing transitions, and to spot gaps in existing policy activities. The case of the Estonian energy system is used to briefly illustrate these possibilities. Methodologically, we demonstrate the value of combining theory-based concept-formation with a systematic literature review, enabling not only a provision of a summary of existing literature but also highlighting systematic gaps in that literature. 1. Introduction The mounting challenge of climate change has led to increasingly urgent calls for rapid and deep decarbonization (SDSN and IDDRI, 2014;Geels et al., 2017a; Rockström et al., 2017). As industrial societies are fundamentally underpinned by various socio-technical systems (e.g., mobility, energy, food), radical and coordinated changes in their basic mode of operation are called for (Schot and Kanger, 2018; Kanger and Schot, 2019). In particular, work in the sustainability transitions field (Grin et al., 2010; Markard et al., 2012; Köhler et al., 2019) has focused on identifying the preconditions, driving mechan- isms, broad patterns and possibilities for accelerating radical transfor- mations in socio-technical systems. In parallel, there has been a growing recognition in the policy stu- dies and innovation policy fields that sustainability transitions require new approaches. Over the past decade a third generation of innovation policy has been emerging (Steward, 2012; Diercks et al., 2018; Schot and Steinmueller, 2018). While the first generation (dominant in the post-WWII era) focused on the relationship between basic science and its applications, and the second (onward from the 1980s) on accelerating the speed of innovation, the third generation aims to tackle the directionality and goals (Stirling, 2008) of socio-technical systems. Correspondingly, the implementation of policy instruments from each generation can result in either market, structural system or transfor- mational system failures (Weber and Rohracher, 2012). The notion of 'policy mixes' – a set of policy goals, strategies, instruments and policy processes that influence a given sector or system (and ideally support each other) – has experienced a similar shift. Originating from eco- nomic policy literature (Mundell, 1962), it was subsequently adopted by innovation system studies (Soete and Corpakis, 2003; Borrás and Edquist, 2013) and has been increasingly deployed in sustainability transitions literature (Kern and Howlett, 2009; Kivimaa and Kern, 2016). Put together, current literature stresses a need to design, evaluate, and implement appropriate policy mixes to shape the direc- tionality of socio-technical systems while avoiding transformational system failures. The literature on policy mixes in sustainability transitions has made steady progress in the identification and analysis of particular policy instruments (Kivimaa and Virkamäki, 2014), elements, policy processes and desirable characteristics of policy mixes (Rogge and https://doi.org/10.1016/j.respol.2020.104072 Received 11 November 2019; Received in revised form 19 June 2020; Accepted 5 July 2020 ⁎ Corresponding author at: Institute of Social Studies, University of Tartu, Lossi 36, 51003, Tartu, Estonia. E-mail addresses: l.kanger@sussex.ac.uk, laur.kanger@ut.ee (L. Kanger), b.sovacool@sussex.ac.uk (B.K. Sovacool), martin.noorkoiv@ut.ee (M. Noorkõiv). Research Policy 49 (2020) 104072 0048-7333/ © 2020 Elsevier B.V. All rights reserved. T