Asthmatic children age 3-17 from low income households in King County are randomly assigned into a community health worker (CHW) intervention group and a control group. The intervention is in-home education and support related to asthma self-management. The main outcome measures are asthma symptom-free days, caretaker's asthma-related quality of life score, and health care utilization for asthma measured at baseline and 12 months after baseline enrollment.