Steve,
Yep. I don't usually have any trouble, but you do get the aperiodic abuser and I apply the "slow crush."
When it exceeds the proper time, slowly and methodically call, email and let them know that there will be repercussions at a specific deadline. That has worked very nicely for me in the past; especially when you stay calm and document each attempt to get paid. I also told them I would reach out to everyone on the "client list" on their site to let them know.
Do I care about working for them in the future, not so far. The British Museum was another of my infrequent offenders. They were quire surprised when I told them I would be sending messages to the local museum, The Walters, where I had done the work. I think it also helped that I contacted the British Museum's marketing and PR people to let them know where I was headed.
Regards,
Ty Ford

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