A system for automated adaptation and improvement of speaker authentication in a voice biometric system environment, comprising a speech sample collector, a target selector, a voice analyzer, a voice data modifier, and a call flow creator. The speech sample collector retrieves speech samples from a database of enrolled participants in a speaker authentication system. The target selector selects target users that will be used to test the speaker authentication system. The voice analyzer extracts a speech component data set from each of the speech samples. The call flow creator creates a plurality of call flows for testing the speaker authentication system, each call flow being either an impostor call flow or a legitimate call flow. The call flows created by the call flow creator are used to test the speaker authentication system.