[AdamGibbins]

Reward early payments.

[rhizome]

This is what I do. I only have one main client, and it's a more-or-less ongoing arrangement, but I invoice on the 1st & 16th and give a percentage discount if they pay within 10 days.

[porlw]

This is a much better idea than trying to impose a late payment fee - set your rates 10% higher, offer a 10% discount on early payment.