Play Safety Forum:
https://playsafetyforum.wordpress.com/

Play England:
http://www.playengland.org.uk/

Play Wales:
http://www.playwales.org.uk/eng/

Play Scotland:
http://www.playwales.org.uk/eng/

PlayBoard N. Ireland:
http://www.playboard.org/

International School Grounds Alliance (ISGA):
http://www.internationalschoolgrounds.org/