ANDI (American nitrox divers international): www.andihq.com

BSAC (British sub-aqua club):  www.bsac.com

BSAC Snorkelling:  www.bsacsnorkelling.co.uk

CMAS (Confederation mondiale des activites subaquatiqus):  www.cmas.org

IAHD (International Association for Handicapped Divers) : www.iahd.org/

IANTD (International association of nitrox and technical divers):  www.iantd.com

NAUI (National association of underwater instructors): www.naui.org

PADI (Professional association of diving instructors): www.padi.com

SAA (Sub aqua association):  www.saa.org.uk/

ScotSAC (Scottish Sub Aqua Club): www.scotsac.com

SSI (Scuba Schools International) : www.divessi.com/