The document discusses writing collection letters to customers with unpaid bills. It provides examples of different types of collection letters to use at each stage of the collection process. The stages include an initial bill or statement, reminder letters sent every week or two, an appeal letter highlighting the customer's advantage to paying, a firm request letter, a final warning letter, and a legal notice letter if payment is not received. For each letter, the key points to include are expressing regret for the unpaid bill, referring to the amount due and previous reminders, and motivating the customer to take action by paying or providing a date of intended payment. The letters should not use insincere, angering, or humiliating language and should avoid official j