This article considers the lives of disabled people requiring assistive technology who live in contexts of urban poverty. Provision is often constrained by a range of contextual factors which seem outside the scope of health and rehabilitation services. We critically reflect on health, rehabilitation, and capabilities approaches. We explore both rehabilitation and capabilities approaches with posture and mobility practice in an area of urban poverty in Argentina. Contrasting rehabilitation and capabilities approaches to a composite posture and mobility case provides a range of insights. Rehabilitation approaches start with the individual as the locus for intervention. Capabilities approaches reframe interventions such as posture and mobility in terms of the freedoms they offer, and highlight the barriers or capability gaps that must be addressed to achieve outcomes. We conclude that capabilities approaches give practitioners the scope to go beyond posture and mobility processes and attend to the other factors, across the ecosystem, that prevent people from realizing their freedoms. To address capability gaps, a broader scope of practice for health practitioners may include consumer empowerment strategies; partnering with the community; and systemic advocacy with duty holders able to address systemic barriers.