A fundamental aspect of the Mental Capacity Act 2005 (MCA) is the statutory endorsement of a functional approach to capacity. In principle, this requires a separate assessment of capacity in respect of each decision to be made. Most capacity assessments take place at a non-judicial level, and, outside of day-to-day decisions, the most common assessors are likely to be healthcare professionals. This paper investigates the practical operation of the capacity assessment process at both judicial and non-judicial levels. It asks whether the process can deliver on the MCA's goal of preserving maximum decision-making freedom, while, at the same time, providing an appropriate degree of protection. It argues that assessors who are not legally trained encounter signific