The collection letters are written to those customers who are failed to make payment after the completion of credit period. While writing collection letters special care should be taken about business relations. The customer with whom firm has been dealing from long time, the past good business relations should be taken into account and reason behind the delay in payment should be inquired. Readiness to help them should be potrayed in the collection letter. The new customer with whom the firm does not have long term relation, can not be given such liberties. Over and above this, the prestige of the customer firm should also be taken into consideration. In short, while writing collection letters, business relations should be icQpt in mind.