Telecommunication generally is the number-two expense in most organizations; secondonly to personnel cost. Telephone usage typically account for 75％ of this amount. It isgood that organizations depend on telecommunications more as opposed to moreexpensive alternative (such as travel, personnel cost, etc) but the high expenses ontelephone must be checked and reduced. Modern telephone systems provide information useful to help manage these expenses.It is essential to implement a control system to capture and provide access to thisinformation. Call Detail Records (CDR) produced by telephone systems are the basis of CallAccounting Systems: a proven method for costing and allocating telephone expenses.Ordinary "batch" systems process the information at the end of each month. It is thereforedifficult to find out what happens when a hacker gets into an organizations PBX system. This thesis reviews the features of the existing Call Accounting System software andadds new features. The main work of this thesis is the development of two callaccounting systems. Bill-Me is for standalone computers and WebBill-Me is a web-basedcall accounting system. The new features include real time cost accounting, which allowinstant access to all levels of detail and swninary reports, and the ability to generate acomplete telephone bill on demand by a user. Users could also use their account code tologin to the organizations Call Accounting System database and query the database ontheir own for the detail report of the calls they have been making. These new features will help improve the existing Call Accounting System software, andenable management of organizations to make decisions to drastically reduce telephonecall expenses. Information on telephone calls are made easily available to users to helpthem reduce unnecessary calls made and to restore confidence between management andusers on telephone bills.