Introduction: Asthma is a common condition affecting many children in child-care centers. The National Asthma Education and Prevention Program offers recommendations about creating an asthma-friendly childcare setting. However, no studies have investigated the extent to which child-care centers adhere to these recommendations. This study describes the development of a novel instrument to determine the ability of childcare centers to meet national recommendations for asthma. Methods: The Preparing for Asthma in Child Care (PACC) Instrument was developed using information from existing recommendations and standards, the peer-reviewed literature, site visits, and expert interviews. The survey questions were pilot-tested at 36 child-care centers throughout San Francisco. Results: The instrument is composed of 43 items across seven domains: smoking exposure, presence of a medical consultant and policies, management of ventilation and triggers, access to medication, presence of asthma action plans, staff training, and encouragement of physical activity. Discussion: The PACC Instrument is an evidence-based and comprehensive tool designed to identify areas to target to improve asthma care for children in child-care centers. (author abstract)