The National Electricity Transmission System Security and Quality of Supply Standards (NETS SQSS) sets out a coordinated set of criteria and methodologies that Transmission Licensees (both onshore and offshore) shall use in the planning and operation of the National Electricity Transmission System. These will determine the need for services provided to the Transmission Licensees. 

The criterion presented in the NETS SQSS represents the minimum requirements for the planning and operation of the National Electricity Transmission System.

Additional criteria, for example covering more detailed and other aspects of quality of supply, are contained in the Grid Code and the SO-TO Code, which should be read in conjunction with this document.

Information relating to all aspects of the NETS SQSS can be accessed on these pages, including documents relating to proposed amendments to the NETS SQSS and information on the SQSS Review Group.