In recent years there has been a move towards a more human rights-based approach to the issue of supported decision-making (SDM) with legislative changes strengthening the formal right of older people and people with disabilities to participate in care planning and decision making. According to the United Nations Convention on the Rights of People with Disabilities (UNCRPD),‘persons with disabilities enjoy legal capacity on an equal basis with others in all aspects of life’ (Article 12). This raises important questions however about how decisions are currently made and experienced in practice throwing up critical considerations for social workers who are required to assist and support individuals whose decision-making capacity may be impaired. SDM is viewed as a key mechanism for delivering the rights of persons with disabilities under the UNCRPD with several commentators highlighting its potential for older people and people living with dementia. SDM endorses the recognition of all persons as the holders of rights, with the entitlement to be at the centre of the decisions that affect them. In this chapter we will give an overview of the concepts of supported, shared and substitute decision making.We will thereafter draw on empirical research in adult social work to provide an in-depth understanding of how SDM can be utilised with older people with multiple health and care needs and how this might be applied in different settings in needs assessment practice. The chapter concludes with a synthesis of current research and thoughts about challenges and the future prospectsof SDM.