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Senior Executive Fundamentals

Westminster system

As a senior executive it is important to understand the system of government you are operating in.

The Westminster system is the basis of government in Australia, at the state, territory and federal level. It is based on the British model of responsible government.

Under this system public sector employees serve the people of their state, territory or country by implementing the government's policies, decisions and programs. This includes:

  • understanding that Ministers and the Cabinet are responsible for deciding policy, and are free to accept or reject the advice of agencies
  • accepting that although executives are under the direction of their secretary or agency head, they have a clear duty to respond promptly and professionally to Ministers’ requests for advice or information
  • providing advice to Ministers that is apolitical, 'frank and fearless’ and non-partisan.

The Westminster system comprises:

  • a head of state - the Sovereign or their representative 
  • an elected parliament, made up of one or two houses
  • a government formed by the political party or coalition that has majority support in the lower house of parliament
  • a Prime Minister or Premier, who heads the government
  • a ministry, drawn from members of parliament – usually members of the government – who exercise executive authority and are accountable to the parliament
  • an independent judiciary
  • an apolitical professional public sector that provides the government with impartial advice and implements the government's policies and programs.

Separation of powers

At the heart of the Westminster system is the concept that power is separated between the three branches of government, creating a system of checks and balances. These branches are:

  • the legislature: the parliament, which makes the laws
  • the executive: the Governor, Prime Minister, Premier, Ministers, departments and agencies, which are responsible for implementing laws
  • the judiciary: the courts, which interpret and apply the law.

The separation of powers is considered one of the cornerstones of our democracy. In Australia’s Westminster system of parliamentary democracy, the separation is not total because the executive is drawn from and accountable to the legislature.

The separation of powers diagram
Text description of above diagram

The image diagram outlines the following:

  • The Crown contains the Governor (Sovereign representative) and links to 3 areas:
    • Parliament
    • Executive
    • Judiciary
  • Parliament contains Legislative Council and Legislative Assembly (both link to one another)
  • Executive contains a structure as follows:
    • Executive Council is the link to and from the Crown.
    • Executive Council also links to and from the Premier and Ministers.
    • Premier and Ministers link to 3 areas:
      1. Parliamentary Secretaries
      2. Public sector
      3. Ministers’ Officers
  • Judiciary contains NSW Courts

Parliament of NSW

The Parliament of NSW is the law-making body for the state, directly elected by the people to make state laws, control state finances, and discuss matters of importance to the people of NSW. The Parliament of NSW consists of two democratically elected houses: the Legislative Assembly (lower house) and the Legislative Council (upper house). There are 135 members of the NSW Parliament: 93 in the lower house and 42 in the upper house.  

Government of NSW

Parliamentary elections determine the government of NSW, which is formed by the party with majority support in the Legislative Assembly. The Governor of NSW commissions the NSW Premier and Ministers, also referred to as the Ministry, to be responsible for the day-to-day administration of the state. The Ministers are collectively and individually responsible for government policy and actions.

Premier of NSW

The Premier is the head of the Government. They lead the party or coalition that has majority support in the Legislative Assembly (the lower house). They advise the Governor of NSW on the appointment of Ministers, determines the makeup of agencies, and allocates legislation to Ministers.

NSW Cabinet

The Premier and appointed Ministers together constitute the Cabinet, which decides the government’s priorities, policies and legislative program.

Ministers bring their proposals to Cabinet, which then makes decisions that are collective, confidential and binding on Ministers.


Under the Constitution Act 1902 (NSW) (the Constitution Act) the Premier and Ministers are appointed by the Governor. The Premier identifies and allocates the ministerial portfolios and recommends to the governor that the selected people be appointed.

Ministers decide on policy and are accountable to the Parliament for their decisions. One convention of the Westminster system is ministerial responsibility, whereby Ministers administer and bear responsibility for the actions of an agency within their control.

Ministers’ parliamentary duties include:

  • answering questions from other members of parliament during question time in the Legislative Assembly or the Legislative Council
  • responding to questions on notice from other members of parliament
  • the passage of bills for which they are responsible through their house of the parliament
  • appearing at budget estimates inquiries.
  • providing government responses to recommendations of committee inquiries.

The Premier may appoint a Minister to help them or other Ministers carry out their responsibilities. This assistance may include receiving deputations, attending meetings and functions, and handling correspondence. The Governor commissions these appointments. All appointments to or changes to the ministry are published in the NSW Government Gazette on the day of approval.

Ministerial portfolios

The Constitution Act does not prescribe a minimum or maximum number of Ministers. The number of Ministers is determined by the Premier. If the number of portfolios the Government wishes to recognise is greater than the number of Ministers, some Ministers may be given more than one portfolio.

The Premier may change the titles and groupings of portfolios from time to time to emphasise policy initiatives or in response to community expectations or needs. These changes are known as machinery of government changes and they may have an impact on your work.

For more information on the Minister responsible for each piece of legislation, see the Allocation of the Administration of Acts.

Public sector

Another key element of the Westminster system is a permanent public sector. Secretaries and heads of agencies are responsible for the general conduct and management of their agencies. Public servants are appointed on merit, and all are required to act in accordance with the sector’s core values of trust, service, accountability and integrity.

Public servants work under the direction of their secretary or agency head. Within this context they support Ministers' efforts to:

  • develop and advise on policy options and draft legislation
  • implement the Government’s decisions, policies and programs
  • deliver services to the community
  • manage the state’s resources, assets and finances.