Disability is understood, defined and measured in many different ways, with variations both within and between countries. Far from being a matter of academic interest only, the particular way in which the concept of disability is interpreted can determine how disabled people are perceived by others in society, and often has a direct impact on development policy and practice. Where disability is viewed primarily as a medical issue, for example, interventions designed to support disabled people are likely to centre on medical solutions. Alternatively, where disability is thought to arise from discriminatory practices, stigmatising beliefs and negative attitudes within society, interventions are more likely to focus on promoting disability rights and advocating for societal change.