A cabinet secretary is usually a senior official (typically a civil servant) who provides services and advice to a cabinet of ministers as part of the Cabinet Office. In many countries, the position can have considerably wider functions and powers, including general responsibility for the entire civil service.

The title of cabinet secretary may also be used as an alternative term for a politically appointed cabinet minister, derived from secretary of state—the formal title for ministers. This naming convention is used in Japan, Kenya, Scotland and the United States.

In Australia the equivalent position is the Secretary of the Department of the Prime Minister and Cabinet, although both the department and its secretary have wider responsibilities than in most other governments derived from the Westminster System.

Prime Minister Scott Morrison established a position entitled Cabinet Secretary in August 2019 within the Prime Minister's Office responsible for cabinet operations and appointed a former senior political adviser and intelligence official Andrew Shearer to the role.

The Cabinet Secretary is also a title conferred on an Australian minister responsible for assisting the prime minister to manage the day-to-day procedural and operational matters of the Cabinet and any Cabinet committees. As per all other ministers in the Westminster system, the Cabinet Secretary is a sitting member of Parliament, chosen by the Prime Minister and officially appointed by the Governor-General. The Cabinet Secretary is a portfolio minister of the Department of the Prime Minister and Cabinet and has existed at various stages since 2007.

Australia's states and territories have equivalent officials

In Canada the equivalent position is the Clerk of the Privy Council, who functions as Deputy Minister to the prime minister of Canada and heads the Privy Council Office. Canada's provinces and territories also have equivalent officials as the head of their respective public services, as in the list below:

The Cabinet Secretariat is under the direct charge of the Prime Minister. The administrative head of the Cabinet Secretariat is the Cabinet Secretary who is also the ex-officio Chairman of the Civil Services Board, and thus the head of the Indian Administrative Service. As a matter of convention the senior most civil servant is appointed as a Cabinet Secretary. He or she belongs to the Indian Administrative Service. The incumbent generally has a tenure of two to three years. Though there is no fixed tenure. His or her tenure however, can be extended. The Cabinet Secretary is the head of all the civil services under the constitution which is the All India Civil Services and the Central Civil Services (Grade A and Grade B). His status in the Indian order of precedence is equivalent to that of the Attorney General of India and just above chiefs of staff or equivalent in the armed services holding the rank of full general.