There is now a reasonable body of data that would suggest that the immunopathology of asthma is similar, if not identical, in childhood asthmatics compared with adult asthmatics. Indeed, we now have evidence that much of the immunopathology is established within the airways of asthmatics very early after the onset of symptoms and, given the lack of correlation with duration of symptoms, may even antedate the first manifestations. There are, however, some differences with neutrophil recruitment being somewhat more prominent than has been recorded from adult observations. The utility of any inflammation parameter in identifying the real future asthmatics has yet to be studied in sufficient detail to define sensitivity, specificity and predictive value. Such studies will be an essential prerequisite to establishing very early intervention strategies, particularly if these involve the use of inhaled and/or oral corticosteroid.