Caller identifying method, program, and apparatus and recording medium

A caller number received from an exchange machine by a telephone coordination server (CTI server) is noticed to a customer database to search for caller information. When pieces of caller information are acquired from the customer database by the telephone coordination server, the exchange machine is connected to a voice automatic response device (IVR device) to acquire predetermined voice data by telephone communication with a caller, and the voice data is compared with voice data included in the caller information by a voice recognition server to generate caller candidate information having priority levels. On the basis of caller candidate information, caller information of a first candidate is displayed on an operator client, candidate names of second and subsequent candidates are displayed as a list, and an operation of selecting a candidate in the displayed list is caused to change the caller information being displayed at the present into caller information of a selected candidate.