The brochure entitled The International System of Units is the essential reference for all those who wish to use the SI correctly. It contains the official definitions of the base units of the SI, and all the decisions of the CIPM and CGPM related to the SI, its formalism and use. The brochure is periodically updated after detailed discussion by the Consultative Committee for Units (CCU).

		The brochure is published in English as well as the official French. The most recent edition, the 8th, was published in May 2006. The text is browsable on-line. The brochure can also be downloaded free of charge in PDF format:  Complete brochure (8th edition)  Text in English (8th edition)  Text in French (8th edition) Printed copies of the brochure may be obtained on application from the BIPM.