With the advent of responsible government in 1890, the Governor was superseded as the Chief Executive Officer of Western Australia by a Premier and Cabinet who were responsible to Parliament. The first Premier was the Hon. John (afterwards Sir John and later Baron) Forrest, who held the position until 1901. Premier Forrest's office was managed by Frederic D. North, a clerk from the Crown Lands Office who was appointed Secretary and Clerk to the Executive Council in February 1891. North may be regarded as the instigator of the Premier's Department since it was his submission to Forrest which led to the creation of the Department in May 1898.

At its inception, the Department consisted of North (who was styled "Under Secretary"), a shorthand clerk, a records clerk and a messenger. When the Department was first established in 1898 it was gazetted as a sub-department of the Treasury. In July 1901 it became a sub-department of the Attorney-General's Department. A year later it became a sub-department of the Colonial Secretary's Department.

In August 1903 the title of the Premier's "Department" was changed to Premier's "Office", and during the next few years the office was located within the Departments held in the portfolio of the Premiers of the day.

In 1907, the Premier's Secretariat was recognized as a separate entity and was allocated its own appropriation. For the next 34 years it functioned as an autonomous government Department.

In August 1941 it reverted to being a sub-department of the State Treasury. However, its status was restored in January 1948 and since then it has functioned as an independent Department. The changing status names and affiliations of the Department may be summarized as follows:

• May 1898: Premier's Department - sub-department of the Colonial Treasury;

• July 1901: Premier's Department - sub-department of the Attorney-General;

• July 1902: Premier's Department - sub-department of the Colonial Secretary's Office;

• August 1903: Premier's Department - located within various departments, mainly Treasury;

• January 1907: Premier's Office - autonomous department;

• August 1919: Premier's Department - autonomous department;

• August 1941: Premier's Office - sub-department of State Treasury;

• January 1948: Premier's Department - autonomous department.

On 1 September 1987 the Department was reorganized and its name changed to the Ministry of the Premier and the Cabinet.

The organisation is known now as the Department of the Premier and Cabinet.

Just as the name of the Department changed, so too did the title of Departmental Heads. The permanent Head of the Department was known variously as "Under Secretary, Premier's Department" (1898-1903); "Secretary to the Premier" (1903-1919); "Secretary, Premier's Department" (1919-1936); "Under Secretary, Premier's Department" (1936-1941); "Secretary, Premier's Office" (1941-1947); and "Under Secretary, Premier's Department" (1948-1987).

In 1917 the Premier's Department assumed responsibility for the office of the Agent-General in London. The Department subsequently administered other agencies including the Government Motor Car Service, Government Printer, Public Service Commission, Railway Advisory Board and the State Gardens Board (afterwards known as the National Parks Board). During the Second World War, when the National Security Act vested the Premier with wide powers, the Department was responsible for such matters as blackouts, hotel hours, race meetings and basic wages.

Later, the Department was to hold responsibility for Royal Commissions and other Commissions of Inquiry, for protocol and for the appointment of Justices of the Peace. As well as providing secretarial and administrative assistance to the Premier and the Executive Council, the Department acted as a liaison between the Government and the Governor and between the Legislature and the Judiciary.