Traditional healers' practices are widespread around the world, yet their diagnostic skills have rarely been investigated. This exploratory study examines whether yachactaitas (Quichua healers) in the Andes identify cases of psychiatric illness in their communities. For over 18 months, ten yachactaitas participated in the identification of 50 individuals with the condition known as llaqui. Medical and psychiatric evaluation indicated that most of those so diagnosed had a DSM-III-R mental disorder. None of the participants with llaqui was considered healthy in biomedical or psychiatric terms. It is suggested that yachactaitas might indeed identify general psychiatric cases in their communities, and that this might be useful for screening purposes.