Chronic cough in children represents a diagnostic challenge. This study evaluates the outcomes of a simple diagnostic approach that uses a positive response to therapeutic trial of asthma with short course of oral steroids as a diagnostic test if history and physical examination indicate no other illnesses. Electronic records of initial evaluation and follow-up visits were reviewed for all patients presenting with chronic cough to a Pediatric Allergy and Pulmonary clinic between 1995 and 2001, where such diagnostic approach has been undertaken. If a patient was lost to follow up, a phone call was attempted to complete records. A total of 69 patients were eligible. Median age at presentation was 3 years (range 0.3-15). Final diagnosis was reached in 54 (75%) patients, 39 of which (72%) were confirmed to have asthma. Other diagnoses included gastroesophageal reflux in 3, pertussis in 3, airway malacia in 3, habit cough syndrome in 2, cystic fibrosis in 1, primary ciliary dyskinesia in 1, foreign body aspiration in 1, and Arnold-Chiari malformation in 1. Forty-four patients (80%) were given a different diagnosis from their pre-evaluation diagnosis. The average number of tests done on asthma patients was 2 and for non-asthma was 2.9. All asthma patients improved with treatment. Therapeutic trial with oral steroids is an effective tool in evaluating chronic cough to reach the diagnosis of asthma, resolve symptoms quickly, and minimize extensive testing.