During the last few years, "Mobility as a Service" (MaaS) has been conceptualized and researched as a platform for integrated, mixed-mode mobility. While some hope it will lead to environmental benefits, its real effects are still unclear. Here, we explore how MaaS is related to, and can be combined with, the established "Avoid-Shift-Improve" transport planning approach (ASI). We see that the MaaS concept described in research does not support "Avoid"-ing unnecessary transport. We combine learnings from MaaS research with learnings from a living lab, where mobility services can be booked in combination with a local co-working hub for commuters. In both literature and living lab, we especially examine the role of public authorities for ASI inMaaS. We conclude that more research is needed on howMaaS can be guided by ASI, and suggest that non-travel accessibility services, such as coworking hubs, could be part of the MaaS concept to support "Avoid"-ing unnecessary transport. Furthermore, we suggest that urban form needs to be considered in MaaS research. We also see that public authorities have an important role to play in ensuring that MaaS serves ASI and sustainable mobility.