The problem of SETI (Search for Extraterrestrial Intelligence) began to interest him in the second half of the 1970's. He listened to the debates of Sklovszkij, Sagan, György Marx and others about the various observation strategies to be followed and read progressively more about the possibility of us having companions in the Universe. After having spoken a number of times on the issue, in 1982 he was selected as a member, and in 1986 co-president, of the SETI committee, founded in 1966 by the International Astronautics Academy. He was co-president with John Billingham, then Jill Tarter until 2001 and one of the organisers of the annual symposiums.
From its initial stages, he has been a member of the Bioastronomy Committee of the International Union of Astronomy, founded in 1982. In the 1990s he formed part of its leadership. He lectured at the majority of the symposiums organised every three years. Gradually it became his conviction that there are few more important current scientific problems than this, which greatly affect how we view the world.