This article considers attempts to include the issues of ageing and ill health in a Rawlsian framework. It first considers Norman Daniels’ Prudential Lifespan Account, which reduces intergenerational questions to issues of intrapersonal prudence from behind a Rawslian veil of ignorance. This approach faces several problems of idealisation, including those raised by Hugh Lazenby, because it must assume that everyone will live to the same age, undermining its status as a prudential calculation. I then assess Lazenby's account, which applies Rawls’ general theory of justice more directly to healthcare. Lazenby suggests that we should apply Rawls’ difference principle – which claims that any inequalities in social goods must benefit the worst off – to conclude that we should significantly prioritise treatment of young patients. I argue first that the existence of young terminally ill patients undermines a number of Rawlsian arguments for the difference principle. I then argue that the structure of ageing undermines the Rawlsian decision mechanism of the ‘veil of ignorance’ on which Lazenby relies. I conclude that age and terminal illness present significant problems for any comprehensive Rawlsian account of justice.