Quaternary industry is a component of the economic system that includes all intellectually based professions and activities. It is more commonly referred to as the quaternary system.
The components of the economic system include the primary, secondary, tertiary, quinary and quaternary sectors. The quaternary sector of the economy provides knowledge-based services. It is primarily focused on industries of technology, scientific research and education. The quaternary section is sometimes included in the tertiary sector due to its service-based nature, although the specificity of the quaternary sector's functions allows it to function as a separate sector. The quinary sector may be considered a branch of the quaternary sector as it focuses on high-level decisions made by executives in quaternary industries.
Companies such as pharmaceuticals involved with the quaternary sector commonly work on investments that help them expand, as well as make improvements to make production methods and manufacturing more efficient. They gather information that is essential to understanding economic trends and which investments can bring the highest profits and growth. Media and other forms of entertainment industries are also included in the quaternary sector and are referred to as "pure" services. In economies such as that of the United Kingdom and United States, the service-based industries included in the quaternary and tertiary sectors are the primary employers, making them an essential component to the economic system.