Numerous attempts of implementing transition pathways across Europe illustrate the difficulty of designing policies that combine efficient climate action and justice considerations. One reason is that the socially diverse, and thus also geographically dispersed demands and vulnerabilities of potentially affected groups do not appear as a well-structured input at any stage of the policy-making process. Therefore, TANDEM will test an innovative transdisciplinary approach in five different case studies in Spain, Belgium, Finland, Poland and Austria that address controversial transition policies in energy and mobility affecting urban and rural populations. The TANDEM project aims to design a methodology allowing policy makers to create and implement inclusive and just transition pathways by involving potentially affected citizens, public authorities, the private sector and other relevant stakeholders. It relies on combination of accessible and complementary methods: deliberative visioning build on art-based approaches, system mapping, assessment and appraisal methods. These methods constitute the backbone of a series of three deliberation panels with citizens. In these panels TANDEM invites participants to create their visions, perspectives and narratives on just transition policies and to define their own criteria and interventions. This deliberation process will guide a systemic impact assessment that will inform individual appraisals of the interventions. Public authorities will be involved at the beginning and end of each panel to provide insights on political, social and economic factors that should be taken into consideration. Furthermore, private companies will be invited to participate through interviews and surveys. TANDEM will thus develop a transdisciplinary approach to identify and analyse emerging inequalities of low-carbon transition policies, as well as to co-design socially fair and effective alternative transition pathways with stakeholders.