Mike Monteiro: Fuck You, Pay Me [video] (2011)

The same. If the company does not adhere to previous agreements it is rotten anyways and I quit working for them and write off the unpaid month. But, two important things: 1. of course the agreement to work for them is there in written form, with the most basics confirmend by both parties, like: hourly rate, payment window, liability waiver 2. if there are graphic assets in play: permission to use my assets only granted if they have been finished by me and if the rates for finishing have been paid. So if they stop paying me they have a half finished asset without permission to use it.

Added: forgot to mention that as a safeguard I let companies sign off on my hours on a weekly/biweekly basis. Until now every company that did not want to pay also stopped signing off my hours. If signing my hours takes longer than a week (important: always communicate this in a professional manner and beforehand!) I immediately stop working for them until they either sign off in the next three weeks or we part ways. Don't fall for "important person not here for a month". If there is no one else around to sign sth for a month, company is lost anyways, no need to invest any more effort.