Chairmain, British Interplanetery Society 1947-50, 1953        Hon. Chairman, Society of Sattellite Professionals               
        President:
                British Science Fiction Association.          Life Member: Association of British Science Writers    Hon. V/President, H.G. Wells Society        
        Patron:
             Arthur Clarke Centre for Modern Technologies, Sri Lanka  Sri Lanka Association for the Advancement of Science  Sri Lanka Astronomical Association Sri Lanka Animal Welfare Association Sri Lanka National Institute for ParapledgicsScience Fiction FoundationAstronomical Society of FoundationAstronomical Society of HaringeyBritish Sub Aqua-ClubCouncil Member:Society of AuthorsAdvisory Council: International Science Policy FoundationFauna International (Sri Lanka)Earth Trust
        Board Member:
          National Space Society (USA)Space Generation Foundation (USA)IAU (SETI) Commission 51The Planetary Society (USA)Lindbergh Award Nominations Committee (USA)Buckminster Fuller Institute 
        Trustee:
            Institute of Integrale Education (Sri Lanka)