Urban minority families with children with asthma often live in homes with allergen and irritant exposures harmful to these children. We enrolled 392 African-American asthmatic children, male and female, aged 5 to 12, from 42 schools in Washington, DC and Baltimore, MD. The project is designed to test the effectiveness of school-based asthma education interventions, community-based asthma health workers' programs, and the combination on these children. Baseline telephone interviews were carried out with the primary home care-givers for demographic data and for environmental home exposures that exacerbated asthma. Exposures stated to cause wheezing in the children were cigarette smoke in 72%, dust in 53%, cats in 34%, dogs in 27%, and roach exposure in 15%. Fifty-six percent of children live with cigarette smoke exposure, 73% of which is from mothers. This was a highly symptomatic group with 44% reporting two or more days per week of restricted activity and 62% reporting two or more episodes of night symptoms per week. Those with mattress covers on beds had significantly fewer emergency department visits in the past 6 months than those without covers. Over one-third of parents reported children taking two bronchodilators without anti-inflammatory agents. Less than 20% were reported using anti-inflammatory medications. Decreasing asthma severity in this population entails the prevention and control of known risk factors in the home environment. Emphasis must be placed on cigarette smoking cessation programs, covering mattresses, and dust and animal dander control. Primary care physicians require education on the role of anti-inflammatory medications.