The prevalence of asthma in Latin America is reviewed. There are many limitations to using official national statistics, and the data presented are from surveys of restricted populations in Uruguay, Peru, Mexico, Brazil, Venezuela, Argentina, and Chile. Asthma prevalence appears to be quite variable, ranging from 0.4 percent in Peru to 4.3 percent in Brazil. As reported elsewhere in the world, in children rates were higher in boys than girls, and elderly asthmatic patients have higher rates. Further information on the clinical and etiologic characteristics of asthma in Latin America are presented from a survey of chronic allergic disease conducted in seven Latin American countries. Pre-coded forms were completed during consultations at cooperating allergy departments, and all were analyzed centrally at the Pan American Health Organization. Eighty-six percent of the patients studied were atopic and 46 percent of asthmatic patients had a history of other associated allergic conditions (allergic rhinitis, atopic dermatitis). This is higher than reported for developed countries.