ABSTRACT: Functional electrical stimulation (FES) is a widely used and effective intervention for improving gait and quality of life. However, as clinicians, we often encounter situations where we are unsure of a person’s potential to use FES, from the point of view of their mental capacity.The difference between cognition and mental capacity should be distinguished carefully. Adequate cognition, for utilising FES and to comply with treatment programmes is, for many of us, a prerequisite for use when accepting referrals and assessing users’ potential. Mental capacity should be a separate and distinct consideration.The Mental Capacity Act (2005) is a law designed to protect and empower people, related to making decisions about their care, and also to protect the healthcare professionals looking after them. As clinicians, we have a duty to comply with the act, and clinical decision-making in this context can sometimes be challenging.In Sheffield, we have had several occasions where the issue of mental capacity has not been clear-cut. Our experience has generally been positive in finding solutions to potential problems and successfully setting up FES to assist walking in this context.This presentation will briefly review the principal features of the mental capacity legislation and use clinical case studies, supported with video, to illustrate the practical application of these principles in the successful use of FES to address walking and improve function.It is hoped that the presentation, and the discussion generated, will be helpful in informing the clinical application of FES and also be applicable to rehabilitation in a wider context.