This chapter examines the relationship between the UK Parliament and the devolved legislatures established in Wales, Scotland, and Northern Ireland. It first considers the impact of devolution on parliamentary sovereignty before discussing the establishment and development of the devolved parliaments in Wales, Scotland, and Northern Ireland. It then describes the key features of those devolved institutions and the way in which Parliament's interactions with them have evolved since their inception, as well as the division of powers between the United Kingdom and devolved governments. It shows that the influence of Parliament on devolution in the UK has so far been marginal, and that these subtle changes in practices at Westminster point to Parliament as an increasing reflection of wider shifts in public attitudes about the relationships between the territories of the United Kingdom, especially after the Brexit referendum.