I've found it really effective to invent an in-house, debt collection agent. Usually named Boris, Thor or Moose. He contacts late clients directly from our bill

I've found it really effective to invent an in-house, debt collection agent. Usually named Boris, Thor or Moose. He contacts late clients directly from our billing dept, and is a little more insistent than I'd been up to that point. Whether the delinquent client takes him more seriously, or just finds the whole process humorous, I don't know, but it works.