Early childhood wheezing is associated with asthma later in life. However, the high spontaneous recovery rate and the lack of firm predictors for persistence of wheezing complicates the development of evidence-based guidelines for long-term management of wheezy infants and toddlers. Our aim was to define variables that could be used to identify wheezy individuals younger than 3 years of age who would continue to be symptomatic at school age. The method used was a questionnaire-based cross-sectional survey of 2,027 randomly chosen, 6-13-year-old school children. Altogether 1,829 (90%) questionnaires were returned. Emergency medical care had been sought for 186 (10.2%) children for wheezing during the first 3 years of life, and only 17.2% of these children had received similar emergency treatment during the 12 months preceding the survey. The total proportion of children with current asthma at school age was 11.4%. A logistic regression analysis indicated that for the early wheezers, a family history of asthma, an itchy rash or food allergy, and exposure to tobacco smoke at home before the age of 3 years, were all independently associated with symptom persistence until school age. Among all wheezy children younger than 3 years, those who have a history of food allergy, itchy rash, asthma occurrence in a sibling or parent, or are exposed to tobacco smoke during the first years of life are at highest risk for symptom persistence until school age.