The various past and current K-SADS editions are reviewed, as is the literature that describes their uses. This review shows that three DSM-IV-compatible versions of the K-SADS are in general use, one present state (K-SADS-P IVR) and two epidemiological editions (K-SADS-E and K-SADS-P/L). All three interviews provide a current diagnostic assessment. The K-SADS-P IVR also evaluates the worst past episode during the preceding year, and the K-SADS-E and-P/L provide a lifetime diagnosis. The K-SADS-E and -P/L are primarily categorical diagnostic interviews, and the K-SADS-P IVR, which also measures symptom severity, can be used to monitor treatment response. All editions have good rater reliability; however, the quality of the validating data set for the K-SADS is limiting. The author concludes that the K-SADS is a viable interview schedule for assessing current, past, and lifetime diagnostic status in children and adolescents. It has the potential to further assist in the validation of psychiatric disorders. The substantial rater training required for reliable administration and the need for more validation work remain its drawbacks. 4 tables and 39 references