The right to equal recognition before the law, protected by Article 12 of the United Nations (UN) Convention on the Rights of Persons with Disabilities (CRPD), mandates the use of supported decision-making practices to enable disabled people, particularly those with intellectual and/or psychosocial disabilities, to enjoy their legal capacity. Finding ways to translate this theoretical mandate into practice poses a number of particularly challenging socio-legal issues, which this research seeks to address. The English Mental Capacity Act 2005 (MCA) sets out a right to support with decision-making (s.1(3)), underpinned by a presumption of capacity (s.1 (2)). Qualitative interviews with intellectually disabled people, their supporters, and care and support professionals were undertaken to explore how disabled people make decisions in their everyday lives, the kinds of support they need, and the strategies for supported decision-making used in practice. Analysis of these interviews suggests that a range of supported decision-making techniques have been developed in practice and are effective in supporting everyday preferences and some life choices. Paradoxically, it appears that as decisions become more complex, the support available to disabled people reduces. Specifically, much less support is available for more difficult decisions around finances, healthcare and legal matters. We argue that the reasons for this are due to a web of regulatory, social and policy issues. We conclude that implementing the right to enjoy legal capacity through supported decision-making will require a combination of regulatory reform, social change and policy amendment.