sophistication of the environment. At a minimum, we can expect that each system will provide at least a monthly refresh of all pertinent information. Billing System Feeds The data warehouse will probably not be called upon to feed information into the billing system. However, the billing system will be, by far, the single largest contributor of information to the warehouse. All of the revenue, product utilization, and promotional information about customers will come from there. After all, the billing system is the system of record for customer economic activity. The rate at which the billing system is able to provide information to the warehouse will most probably be dependent upon the billing cycles that are run. For the most part, real-time updates will be economically unfeasible, but monthly refresh should be imminently practical. Call Detail Record Feeds In reality, there is no need for any direct call detail information in the master customer data warehouse itself. What is required, however, is a place where call detail records can be processed and summarized. The results of that summarization and exploration activity will be fed to the warehouse. Call Center, Campaign, and Contact Management System Feeds The other major customer touchpoint systems - the call center-, campaign-, and contact-management systems along with any other transaction-based operational systems, all need to have strong, eXcellence in Telecommunications The Telco Churn Handbook intimate, and timely interfaces with the warehouse. Each of these systems holds information about customer contacts that needs to be summarized and stored in the warehouse for access by the other business units. At the same time, each of these systems needs to collect the pertinent contact information that other systems have gathered and use that data to update their own customer profiles. In addition to this transaction-based interface, the customer data warehouse needs to continuously update the segmentation and customer status information that each of the tra