How many colours?

Deciding how many different colours someone should take when they come into the needle exchange should be fairly straight forward – it depends on how many people they're picking up for.

If they're just collecting for themselves, then they'll normally only take one colour (although they might want to take a few of another colour if other people ever inject around them).

A couple would normally pick up two colours, and where people might have a number of other injectors using their equipment they may pick up more of one colour (to use for themselves) and a selection of the other colours.