Across metropolitan regions, traditional public transport struggles to serve territories that are dispersed, low-density, or socially vulnerable. The Lisbon Metropolitan Area (LMA) illustrates both this challenge and the growing role of demand-responsive transport (DRT) as an adaptive mobility solution. This chapter examines how five municipalities in the LMA have experimented with DRT to bridge the gaps left by fixed-route services. It follows the evolution of these initiatives from socially oriented, door-to-door services for elderly residents and people with reduced mobility to semiflexible routes embedded in the metropolitan bus network. Through a comparative analysis of governance models, funding structures, service design, and fare integration, the chapter demonstrates how local context shapes the form DRT takes in the region. An accessibility analysis then reveals where mobility shortcomings persist, highlighting peripheral and fragmented areas where residents struggle to reach healthcare, food retail, and administrative services by public transport. By connecting local practice with spatial evidence, the chapter argues that DRT works best not as a substitute for traditional regular transport, but as a responsive extension of it, one that can strengthen accessibility, inclusion, and resilience in metropolitan mobility systems.