A method for collecting data associated with the voice of a voice system user includes conducting a plurality of conversations with a plurality of voice system users. For each conversation, a speech waveform is captured and digitized, and at least one acoustic feature is extracted. The features are correlated with at least one attribute such as gender, age, accent, native language, dialect, socioeconomic classification, educational level and emotional state. Attribute data and at least one identifying indicia are stored for each user in a data warehouse, in a form to facilitate subsequent data mining thereon. The resulting collection of stored data is then mined to provide information for modifying underlying business logic of the voice system. An apparatus suitable for carrying out the method includes a dialog management unit, an audio capture module, an acoustic from end, a processing module and a data warehouse. Appropriate method steps can be implemented by a digital computer running a suitable program stored on a program storage device.