Issues relating to capacity are increasingly topical and relevant, particularly following the implementation of the Mental Capacity Act 2005. Powers of attorney are one such issue that requires the assessment of capacity for their execution. This article focuses on lasting powers of attorney (LPAs), which were introduced under the Mental Capacity Act in 2007. We describe how LPAs evolved and how they have been used since the inception of the Act. We review salient case law. In doing so, we elucidate pertinent issues for clinicians, particularly in the case of health and welfare LPAs: for the first time in England and Wales, the law allows donors to nominate an attorney to make decisions about their personal health and welfare once they become incapacitated.