Background: There has been an increase in the number and percentage of athletes competing in Olympic Games notifying use of β₂-agonists, from 1.7% at Los Angeles (1984) to 5.5% at Sydney (2000). For Salt Lake City (2002), the International Olympic Committee requested objective evidence to use β₂-agonists for asthma or exercise-induced asthma (EIA). Objective: The objective of this study was to evaluate the evidence submitted for approval to use a β₂-agonist. Methods: Objective evidence for asthma or EIA included (1) an increase of 12% or more of the predicted FEV₁ in response to bronchodilator, (2) a reduction in FEV₁ of 10% or greater from baseline in response to exercise or eucapnic voluntary hyperpnea, (3) a PD₂₀ FEV₁ to methacholine or histamine at a dose of less than 200 μg (2 mg/mL) or less than 1320 μg (13.2 mg/mL) for those taking inhaled corticosteroids for 3 months. Results: There were 165 applications. Of these, 147 (89%) included evidence of a challenge, bronchodilator response, or both, and 163 test results were submitted. One hundred thirty (5.2%) applications were approved. For those with positive responses, the median value (1) was 16.2% of predicted FEV₁ for response to a bronchodilator (n = 13), (2) was a 15.9% decrease in FEV₁ for response to a physical challenge (n = 36), and, (3) for PD₂₀ FEV₁, was 173 μg for response to a pharmacologic challenge (n = 45). Conclusion: The analysis demonstrated that it is feasible to request objective evidence to justify use of β₂-agonists on the medical grounds of asthma or EIA. (J Allergy Clin Immunol 2003;111:45-50.)