Everyone at Lambeth has to wear a different colour lanyard with an ID attached to be allowed into any venue (other than the Marketplace).
It is likely that in photographs in the media you will see people wearing the different colours.
Here is a quick guide to those colours:
Yellow/Gold: Canterbury Volunteers
Grey: Day Guests/Resource People
Purple: Bishops/Bishop's Spouses/Ecumenical Guests
Sky Blue: Press
Dark Blue: University Staff