Within ETSI a specific Industry Specification Group (ISG) on millimetre Wave Transmission (mWT) has been established since January 2015. The group has the task of providing a platform and opportunity for companies and organizations involved in the microwave and millimetre-wave transmission industry, to exchange technical information in order to prepare White Papers and presentations to increase the level of confidence by the operators worldwide in the use of traditional microwave and millimeter-waves. This white paper is one of many technical deliverables produced by ISG mWT about the different aspects of technology, applications, spectrum management, regulation and licensing, which can be found on the dedicated ETSI web site: www.etsi.org/mwt .