The five Nordic countries of Denmark, Finland, Iceland, Norway and Sweden have aggressive climate and energy policies in place and are largely on track in their decarbonisation of electricity, heat, and buildings. Transportation and mobility, however, remains a pressing challenge. This study asks: what are the greatest national and regional transport challenges facing Nordic countries? To provide an answer, the authors conducted 227 semi-structured interviews with participants from 201 institutions across seventeen cities within the Nordic region. Those interviewed represent a diverse array of stakeholders involved with transport technology, policy and practice. Although respondents identified 44 distinct transport challenges, the fossil fuel intensity of transport was by far the most frequently mentioned by more than two-fifths (42%) of the expert sample. Five other challenges were also mentioned the most frequently by respondents: long travel distances (17%), the state of public transport infrastructure (16%), congestion (15%), population density (10%), and electrification of transport (10%). Interestingly, items such as costs and affordability, energy or transport efficiency, consumer knowledge and awareness, and automobile accidents were mentioned by only 3% (or less). The article concludes by what this heterogeneity and prioritization of challenges means for future Nordic research and policy. (C) 2018 Elsevier Ltd. All rights reserved.