Government departments
- Department for Education and Department for Business, Energy and Industrial Strategy: Sam Gyimah resigned as minister of state for universities, science, research and innovation and Chris Skidmore was appointed to the role.
- Department for Business, Energy and Industrial Strategy: Committee on Climate Change – Piers Forster appointed to the committee, replacing Brian Hoskins; Nuclear Decommissioning Authority - Lawrie Haynes appointed chair designate of the new subsidiary body planned for September, Magnox Ltd.
- HM Treasury: The Crown Estate Board – Paula Hay-Plumb reappointed as crown estate commissioner.
- Home Office: Disclosure and Barring Service – Gillian Fairfield took over from Bill Griffiths as chair.
- Department for International Trade: Mark Menzies named as the trade envoy to Argentina.
- Department for Transport: HS2 Ltd – Allan Cook replaced Terry Morgan as chair.
- Foreign and Commonwealth Office: Sir Nicholas Kay KCMG has been appointed as NATO's next senior civilian representative (SCR) in Afghanistan; Philip Rushbrook has been appointed Governor of St Helena, Ascension Island and Tristan da Cunha in succession to Lisa Honan in May 2019.
- Department for Digital, Culture, Media and Sport: Sue Owen to stand down as permanent secretary.
- Ministry of Defence: New appointments from spring 2019: Vice Admiral Timothy Fraser CB is to be promoted admiral and appointed vice chief of the defence staff, in succession to General Gordon Messenger; Vice Admiral Tony Radakin CB is to be promoted admiral and appointed first sea lord and chief of naval staff, in succession to Admiral Sir Philip Jones; Air Marshal Michael Wigston CBE is to be promoted air chief marshal and appointed as chief of the air staff, in succession to Air Chief Marshal Sir Steven Hillier; Lieutenant General Patrick Sanders CBE, DSO is to be promoted general and appointed commander joint forces command, in succession to General Sir Christopher Deverell; Defence Innovation Advisory Panel – Julia King, Simon Segans, Dave Allen and Fiona Murray appointed as members.
Non-Ministerial Departments
- Charity Commission: Tony Cohen, Ian Karet and Nina Hingorani-Crain appointed as board members from 1 January, when Eryl Besse and Tony Leifer will stand down.
Devolved authorities
- Welsh Labour: Mark Drakeford elected as leader of the party, replacing Carwyn Jones.
- Northern Ireland Assembly: Emma Sheerin appointed as the new Sinn Féin MLA for Mid Ulster.
- Welsh Government: Social Care Wales - Arwel Ellis Owen to stand down as chair in July.
Local authorities
- By-election Results 6 December: Highland Council – Alexander MacInnes elected for Wester Ross, Strathpeffer and Lochalsh – SNP gain from Liberal Democrat. (Kate Stephen resigned); Leicester Council – Padmini Chamund elected for Belgrave – Labour hold. (Mansukhlal Chohan died); Oxford Council – Liz Wade elected for Wolvercote – Liberal Democrat hold. (Angie Goff died); Surrey Council – Amanda Boote elected for The Byfleets – Independent gain from Conservative. (Richard Wilson died).
Interest Groups
- Learning and Work Institute: Naomi Clayton and Joe Dromey to become deputy directors of research and development in January.
- Cancer Research UK: Rita Akushie appointed as chief financial officer.
- Action for Pulmonary Fibrosis: Louise Wright named as the new chief executive.