While the effectiveness of bronchoalveolar lavage (BAL) in pediatric therapy has been recognized for years, there are hardly any data on its usefulness in diagnosis, its performance and compatibility in childhood. After 123 bronchological investigations including BAL on 118 children in the age of three months through 16 years, with lavage fluid amounts between 40 and 160 ml, febrile reactions occurred in 17 cases (= 13.8%), i.e. no more frequent than in a group of 100 children bronchologically investigated but without BAL. After blood gas analyses, ECG examinations, blood pressure readings the compatibility of BAL turned out to be good in children of every age. Bronchography pictures after BAL were not reduced in quality, atelectasis formation occurred rarely.