Have you ever received a letter from a debt collection agency? If you have not, then you are among a lucky few people. Failing to pay a bill happens even to those who are financially well-off. For instance, a letter with an open bill can easily slip one’s attention when one is travelling frequently. This is only one reason among many why people don’t pay. Ignoring these can seriously jeopardizes the good relationship with valued customers or even lead to substantial problems. Creditreform has teamed up with Simply Rational, a spin-off from the Max Planck Institute, to design and implement a novel system for debt collection combing Machine Learning and Behavioral Science. The approach has proven highly effective in large-scale field-testing and promises to revolutionize debt collection by taking the individual needs of debtors seriously.