The Essential Services Commission of South Australia (the Commission) was established under the Essential Services Commission Act 2002, which came into effect on 12 September 2002. The Commission is the same body corporate as the former South Australian Independent Industry Regulator (SAIIR), which was previously responsible for some of the Commission's regulatory functions.

The Commission’s objective, specified in the Essential Services Commission Act 2002 (ESC Act) is the:

“protection of the long term interests of South Australian consumers with respect to the price, quality and reliability of essential services”

Essential services are defined as being electricity, gas, water and sewerage, maritime, rail and any other services prescribed from time to time.

In pursuing its primary objective, the Commission is required at the same time to have regard to the need to:

Promote competitive and fair market conduct;
Prevent misuse of monopoly or market power;
Facilitate entry into relevant markets;
Promote economic efficiency;
Ensure consumers benefit from competition and efficiency;
Facilitate maintenance of the financial viability of regulated industries and the incentive for long term investment; and
Promote consistency in regulation with other jurisdictions.
The Commission undertakes a number of functions in carrying out its responsibilities as the South Australian economic regulator. Most of the Commission’s functions cannot be actioned in the absence of specific reference in industry legislation. The table below summarises such legislation in force as at 1 January 2011 for various sectors as well as summarising the nature of the regulatory tasks performed by the Commission in each sector.