Glenn was born in Melbourne and raised in Perth. He attended Thornlie Senior High School and left school at 17 to work as a furniture removalist. At the age of 20 he founded his own business operating road trains throughout regional Australia, before becoming an organiser with the Australian Transport Workers Union in 1991.
In 2004 Glenn was elected as a Senator for Western Australia, and started working to fight for the issues he cares passionately about. He vigorously opposed the Howard Liberal Government’s industrial policy known as ‘Work Choices’, and has fought for better wages and conditions in the transport industry. Glenn has also campaigned overseas to improve conditions in the transport industry, particularly against the Toll Corporation for better working rights for Los Angeles Port drivers.
Glenn also is the chairperson of the Senate Rural and Regional Affairs Committee, and in 2012 he was presented with life membership of the Australian Transport Workers Union in 2012 in recognition of his work both at home and abroad.