We studied smoking status in relation to parental attendance at an asthma education program for child patients of a health maintenance organization. Nonattendance rates were 24%, 42%, and 78% in nonsmoking, one-smoker, and two-or-more-smoker families, respectively, and 33% overall. Only the number of smokers (odds ratio [OR] = 3.1; 95% confidence interval [CI] = 1.8, 5.3) and perceived adverse impact of asthma on the family (OR = 0.4; 95% CI = 0.2, 0.9) were retained in a multivariate model that correctly classified 73% of families; demographic characteristics, frequency of asthma symptoms, and health care use were rejected. There was a tendency for smoking parents to deny that their child had asthma (17% among families with two or more smokers; 9% among nonsmoking families). Asthma education programs may fail to involve parents who smoke.