118 schoolchildred (males:females = 2.5 : 1) with bronchial asthma--defined as recurrent allergic or non-allergic expiratory dyspnoea--were investigated as regards their clinical course, frequency of asthma attacks, exercise tolerance, anti-asthmatic drug requirements and spirometric changes during and after participation in specialized holiday programmes during the summer months in 1974, 1975, and 1976. Clear-cut improvement was observed with regard to asthma attack frequency (up to nearly 100%) and drug requirements (up to 76%). Steroid dependence was observed in most cases. No significant spirometric improvement was demonstrable. All data require critical evaluation and interpretation in view of seasonal variations in asthmatic manifestation and the influence of environmental factors. On reviewing the results it is concluded that treatment of the asthmatic child by supervised high altitude holidays (1400 m above seal level), combined with physical training and a respirator re-education programme, is still a justified therapeutic approach, but it cannot replace specific therapy laid down on the basis of careful diagnostic testing. Particpation of the asthmatic child in school gym classes is recommended. Abstention from physical exercis due to a misplaced protective attitude is not beneficial in most cases.