The Kitchen Cabinet is the term used to refer to the advisers and other staff at Number 10 who form the so-called 'inner circle' around the Prime Minister. There is no hard-and-fast rule on the composition or extent of a Kitchen Cabinet, although the larger it is, the more likely a Prime Minister is to draw criticism for being 'Presidential', autocratic and reliant on cronyism rather than the expertise of elected individuals.
Kitchen Cabinets tend to include a chief of staff, heads of policy, government relations and communications and policy and communications advisers, as well as secondees from think-tanks and industry. Most people employed at Number 10 are special advisers or civil servants, although some, such as those charged with political operations, are employed by the Prime Minister's party.
On occasion, Ministers close to the Prime Minister, such as Ministers without Portfolio, might be considered to be part of the inner circle and so might the Prime Minister's PPS. It is often thought that the smaller and more focused policy work of a Kitchen Cabinet provides an antidote to the unwieldy Whitehall machine.
Often the advisers that make up a Kitchen Cabinet use their position at the heart of government as a springboard for a Parliamentary career.
The term 'Kitchen Cabinet' was first used to describe the coterie of close friends and political allies that formed around Harold Wilson in his first term (led by the formidable Marcia Williams, later Lady Falkender). Increasingly since then, it has been used to refer to the Number 10 'machine' as distinct from the Cabinet and Whitehall.