This article takes as its starting point the moral requirement to include persons with serious cognitive impairments in democratic decision‐making. That said, including such persons poses particular practical challenges to effective democratic participation. Nussbaum has set out the most extensive proposals for inclusion based on a model of guardianship, but we find they fall short due to not suitably respecting and facilitating the subjective decision‐making of impaired persons. Instead, we argue for a model of co‐constitution, whereby aides work within a (...) supported decision‐making paradigm to arrive at political choices in collaboration with impaired persons. To flesh out this model, we propose collaboration be based on three ideal types of interaction – expert, Socratic, and deliberative – designed to accommodate differing degrees and types of cognitive impairments. We further argue that the aide should have a relationship of detached professionalism with the impaired person and therefore should not be the person’s carer. Finally, we conclude that this separation be combined with transparent and regular invigilation of the aide’s decision‐making process to best safeguard the process from abuse or error. (shrink)