This paper describes a prototype of a recognition / synthesis system in the Portuguese language. The system was designed to demonstrate an application of the voice-driven database type, consisting of queries to a database installed in a remote computer accessed by the public telephone network. The selected application is a telephone directory service, in which the user requests the telephone number of a subscriber by indicating his first and last names, and the system asks for confirmation of the recognized names before returning the desired information. If requested, a telephone call is made to that particular telephone number. The recognition of the requested names uses a classical DTW technique, and the confirmation software synthesizes the recognized names on the basis of their pre-stored phonetic description, using phoneme concatenation. Preliminary tests with the system show the large potential of this type of applications. Keywords: recognition, DTW, text-to-speech synthesis, phoneme concatenation, voice-driven database