Les Barclay first attended the International Radio Consultative Committee, Study
Group 6 (ionospheric propagation) in 1972.
In 1978 he became international chairman of the study group. He was instrumental
in reorganising the methods of working within the CCIR to respond to the need for
prioritisation, and in adapting the organisation to respond to the transition to
the radiocommunication Sector in the new ITU structure in 1993.
In 1993 he chaired the first Radiocommunication Assembly of the International Telecommunication
Union, and became chairman of new ITU-R Study Group 3 (radiowave propagation) from
1993 to 1997. He is now vice chairman of the ITU-R Co-ordinating Committee for Vocabulary.
He has participated as a UK delegate in various World Radiocommunication Conferences
up to the present, and at ITU Plenipotentiary Conferences.