AN HISTORICAL OUTLINE OF VOICE IDENTIFICATION METHODS IS PRESENTED, AND TYPES OF TESTS AND ERRORS IN CONTEMPORARY AND NONCONTEMPORARY VOICE IDENTIFICATION AND ELIMINATION SAMPLES ARE DESCRIBED. A SECTION ON ACOUSTICS, PHONETICS, AND THEORY OF VOICE PRODUCTION DISCUSSES A CYBERNETIC MODE OF VOICE COMMUNICATION, ACOUSTIC SPEECH PRODUCTION, SPEECH ACOUSTIC PARAMETERS, AND SOURCES OF VARIABILITY IN VOICE IDENTIFICATION SAMPLES. VARIABILITY CAN BE PRODUCED BY THE TALKERS THEMSELVES OR BY THE TRANSMITTING AND RECORDING CHANNELS. SUBJECTIVE METHODS OF TALKER IDENTIFICATION AND ELIMINATION INCLUDE AURAL EXAMINATION OF VOICES (IN WHICH A LISTNER MAY USE THE LONG TERM OR SHORT TERM MEMORY PROCESS TO ELIMINATE OR IDENTIFY AN UNKNOWN TALKER AS BEING THE SAME AS A PARTICULAR KNOWN ONE), VISUAL EXAMINATION OF SPEECH SPECTROGRAMS (IN WHICH THE USER STUDIES PARAMETERS OF SPEECH WAVES VISUALLY DISPLAYED ON A SPECTROGRAPH THAT PLOTS FREQUENCIES ON A VERTICAL AXIS, TIME ON A HORIZONTAL AXIS, AND RELATIVE INTENSITIES AS DEGREES OF PATTERN DARKNESS), AND COMBINED AURAL AND VISUAL EXAMINATION. BY OBJECTIVE METHODS OF VOICE IDENTIFICATION AUTOMATIC OR SEMIAUTOMATIC, COMPUTERS DETERMINE WHETHER THE KNOWN AND UNKNOWN VOICES BELONG TO THE SAME TALKER. THE PROBABILITY OF ERROR IN VOICE IDENTIFICATION AND THE DISCRIMINATORY ABILITY OF THE MACHINE AND THE EXAMINER ARE CONSIDERED. VOICE IDENTIFICATION BY AURAL AND SPECTROGRAPHIC EXAMINATION (VOICEPRINTING) IS THE ONLY METHOD PRESENTLY USED FOR OBTAINING VOICE IDENTIFICATION IN LEGAL CASES OR CRIMINAL INVESTIGATIONS. LEGAL USE OF VOICE IDENTIFICATION BEFORE AND AFTER 1971 IS EXAMINED. LISTS OF BOTH LEGAL CASES IN WHICH VOICE IDENTIFICATION WAS OFFERRED AS EVIDENCE SINCE 1970 AND OF PROFESSIONAL EXAMINERS WHO CAN PERFORM VOICE IDENTIFICATION AND OFFER COURT EVIDENCE ARE APPENDED. REFERENCES AND AN INDEX ARE PROVIDED. (DAG)