The UK Government Chief Scientific Adviser (GCSA) is the personal adviser on science and technology-related activities and policies to the Prime Minister and the Cabinet; and head of the Government Office for Science.
The Chief Scientific Advisor has a significant public role as the government's most visible scientific expert.
As of 2011, every individual government department has its own departmental Chief Scientific Adviser (CSA). The Department for Health has a Chief Scientist in addition to its Chief Scientific Advisor. The GCSA has no formal management responsibility for departmental CSAs and is free to provide advice to all departments, including those that have their own chief scientific adviser. The GCSA and departmental CSAs sit on a Chief Scientific Adviser's Committee (CSAC), a cross-departmental forum for the discussion of science issues, chaired by the GCSA. The advisor also usually serves as chair of the UK’s Scientific Advisory Group for Emergencies (SAGE).