RITVA ERKOLAHTI, JORMA PIHA, MICHAEL MALING Erkolahti R, Piha J, Maling M. Treatment practices in adolescent psychiatric inpatient care. Nord J Psychiatry 1998;52:519 -526. Oslo. ISSN 0803-9488.The comparison of adolescent psychiatric inpatient care in Finland and in the Chicago area, in the United States (US), provides an interesting opportunity to learn from similarities and differences in current treatment practices between the two countries. In this study we have compared the treatment programs in two very differently based service systems. Many similarities could be found, but the diagnostic system, the length of hospital treatment (Finland, mean 20.7 months; US, mean 2.1 months) and the use of medication (Finland, 39%; US, 64%) differed in these two countries. The results seem to reflect differences in the philosophy and management of the units. The service system has an impact on these factors because inpatient treatment is an expensive and limited resource.Adolescent psychiatry, Cross-cultural, Inpatient treatment, Ser6ice system.