The main objective of this study was to evaluate the reliability and validity of the Schedule for Affective-Disorders and Schizophrenia for School-Aged Children Lifetime Version (K-SADS-PL) in an Israeli sample. Fifty-seven adolescent admissions to two psychiatric units were evaluated with the Hebrew translation of the K-SADS-PL. Inter-rater and mother-child agreement were evaluated for diagnoses, and 31 affective symptoms. K-SADS diagnoses were also compared with two-month unit evaluation diagnoses as a measure of consensual validity. The reliability of assessing psychosocial functioning was also examined. Reliability and validity of diagnoses were good to excellent. Mother-child agreement fared less well on all measures. The use of semi-structured interviews and DSM-IV criteria in an Israeli adolescent psychiatric setting are discussed.