This paper identifies the current practices and challenges related to the planning, management, and operation of microtransit systems as well as the concerns associated with the (lack of) policies in place. Our work focuses on the U.S. experience and is primarily based on an in-depth analysis of six microtransit systems using a combination of quantitative and qualitative data. We investigate and classify the multiple ways public agencies form public-private partnerships to institute microtransit service in their jurisdictions and discuss the relative advantages and disadvantages of the different service delivery models. We also thoroughly examine the contracts public agencies formed with private entities to disentangle the various cost elements associated with the launch and operation of a microtransit system. Our policy discussion emphasizes the lack of sustained funding sources for microtransit and the funding formulas that lead to a reduction or loss of public transportation funding when a jurisdiction replaces a fixed route service with microtransit. We also explain the requirements for ADA compliance in microtransit systems and highlight that service equivalency between disabled and non-disabled riders is not guaranteed when only some of the microtransit vehicles and operators are ADA compliant and certified. In terms of operation practices, we describe the safety risks that microtransit users may face on a day-to-day basis due to algorithm-driven virtual pick-up and drop-off locations, and the unwillingness of some service providers to enforce inclusive practices and ensure that individuals without electronic payment options and smartphones can gain access to the service. Furthermore, we discuss the challenges with balancing supply and demand in microtransit systems, and the need for allowing for both on-demand and pre-scheduled trip requests in order to ensure that critical and time-sensitive work, school, and medical trips are accommodated and prioritized.