There is much uncertainty over whether on-demand ridehailing services, namely Uber and Lyft, will worsen or alleviate existing transportation problems such as congestion, emissions, and inequities in access and mobility. For policymakers, transportation planners, and others in the transportation arena, these unknowns have created uncertainty over which policies would best steer ridehailing toward equitable and sustainable outcomes. To address these uncertainties, researchers at UC Davis assessed how stakeholders from different groups view the possible impacts of ridehailing and the policies that might best address those impacts. The researchers evaluated these questions through in-depth interviews with stakeholders from 38 agencies and organizations throughout California. Interviewees included transportation planners, members of state agencies, and representatives from non-profit organizations and the ridehailing industry. This policy brief summarizes those interviews, as well as findings from the research.