At work we’ve got a 5 colour recycling system in the hallways:

Blue : plastic

Grey : paper / cardboard

Red : glass

Purple : metal

Yellow : metal and glass, but with consignment (cans bottles, etc)

I understand the consignment bit, but the other 4 colours of recycling is taken by the city. Which has single source recycling. Also the recycling in our cubicles is single source…

We also have a brown bins for organics, buckets for batteries, and boxes for electronics. Plus normal waste too.