This Practice Note provides an overview of the structure and legislative framework of Solvency UK. It explains the UK’s implementation of Directive 2009/138/EC (the Solvency II Directive), the implications of the UK’s withdrawal from the EU and the development of the post-Brexit Solvency UK regime, including links to relevant UK legislation and Prudential Regulatory Authority (PRA) rules and related PRA policy materials. For more information about the Solvency UK framework, see Practice Notes: Prudential requirements for UK insurers—introduction, Prudential requirements for UK insurers—Pillar 1 requirements and Prudential requirements for UK insurers—Pillar 2 and Pillar 3 requirements. For a chronological tracker of the development and implementation of the Solvency UK framework, see: Solvency UK—timeline. The requirement for transposition and implementation The Solvency II Directive as amended, in particular by Directive 2014/51/EU (Omnibus II), came into effect on 1 January 2016. Member States were required to bring into force the domestic provisions necessary to comply with specified articles of the Solvency II Directive by 31 March 2015, and to have made those instruments applicable