This is a preprint. The final version will be available in Handbook of Sustainable Transport edited by Curtis, C., forthcoming 2020, Edward Elgar Publishing Ltd. The material cannot be used for any other purpose without further permission of the publisher, and is for private use only. Is micro-mobility sustainable? An overview of implications for accessibility, air pollution, safety, physical activity and subjective wellbeing Dimitris Milakis, Laura Gebhardt, Daniel Ehebrecht, Barbara Lenz Institute of Transport Research, German Aerospace Center (DLR), Berlin, Germany Abstract Micro-mobility (MM) is usually presented as an environmental friendly, flexible and socially inclusive new group of travel modes. This chapter first defines and then explores the social sustainability potential of MM by providing an overview of MM implications for accessibility, air pollution, safety, physical activity and subjective wellbeing. Our results show that MM could enhance accessibility, yet costs, physical ability and technical skills might exclude certain social groups from using such modes. MM modes have no or limited direct CO2 emissions but environmental effects are uncertain if we account for the production of these modes. Road safety could be enhanced due to mutual awareness stimulation, but also compromised due to speed differential between MM and other modes. Physical activity could be increased or reduced depending on whether MM modes are electric or not. Exercising, enjoying the scenery, and having fun could enhance subjective well-being of MM mode users, while perceived safety risk could negatively influence subjective well-being. We conclude that MM sustainability potential should not be automatically assumed and could vary among the different MM modes. We suggest a set of regulatory actions with regards to permission, operation and monitoring of MM systems that could enhance their social sustainability. Keywords: Micro-mobility implications, accessibility, air pollution, safety, physical activity, subjective wellbeing 1. Introduction Micro-mobility (MM) is identified by popular media and scholarly literature as an emerging group of rather small-sized vehicles that could facilitate short-distance trips (mainly first- and last-mile trips) in a flexible, joyful and low-cost way (Tiwari 2019; Clewlow 2018; Kaufman and Buttenwieser 2018; Shaheen and Chan 2016). There is no clear definition of MM, but typically the term refers to vehicles that can carry one or two passengers, especially bicycles, various forms of scooters and small cars (and sometimes segways), often as part of docked and undocked sharing schemes that are based on mobility apps. Micro-mobility is usually presented as a sustainable mobility solution, satisfying travelers’ needs for flexibility, personalized mobility with a low environmental impact and high social inclusion potential (Hwang 2010; Semenov 2017). Micro-mobility modes might also have positive impacts on public transport use (Shaheen and Chan 2016). Yet, early evidence show that (a) e-scooter trips in New Zealand replace mainly trips that would have been undertaken by other sustainable modes such as walking, cycling or skateboard (Fitt and Curl 2019), (b) dockless MM solutions (e.g. bikes, scooters) can create safety conflicts with pedestrians and people with disabilities (Sikka et al. 2019), and (c) spatial availability of MM modes could be solely driven by demand and thus not equally distributed across the city (Smith, 2015; Mooney et al., 2019).