Study hypotheses: 1) A broad panel of EBC measures will distinguish asthmatic children not on inhaled corticosteroids (ICS) from both asthmatic children routinely taking ICS and nonasthmatic controls. 2) Standardized equipment and methodologies for EBC collection, processing, storage, shipping, and pH and mediator measurements can be developed that will eliminate significant contamination from oropharyngeal saliva and allow for shipping and processing at a central site.