In the last decade there has been a growing interest in the questions raised by the auditory identification of persons by victims and witnesses. Within IAFP, the International Association for Forensic Phonetics, this has led to the call for guidelines or criteria for identification procedures such as the voice line-up. Against this background, parallels and contrasts with the more widely studied field of visual identification are discussed, as are a number of (un)resolved issues and/or misconceptions surrounding voice line-up procedure. These include the use of repeated trials, blank trials, familiar vs. unfamiliar voices, the use of actors, verbatim text or transcripts, and the notions of propitious heterogeneity and ecphoric similarity. Accepted notions are critically examined. The dearth of estimator-variable research is noted.