It is estimated that there are 100,000 people living with sickle-cell disease (SCD) in the United States [1]. The most common manifestation of SCD is vaso-occlusive crisis, which is characterized by intermittent, unexpected episodes of excruciating pain. As these episodes often come on suddenly, much of the care for these crises occurs within emergency departments (EDs). Several studies have examined ED use and costs for certain groups of patients with SCD [2-4]. For example, in 1997, Woods et al. [2] found that 85.7% of 7,202 hospital admissions for SCD in Illinois were for patients that came through the ED, and the total charges for sickle-cell admissions in Illinois were found to be $30 million a year. A recent study of healthcare use by children with SCD demonstrated that children insured by Medicaid had higher ED utilization than those with private insurance (57% vs.45%) [5]. The purpose of our study was to provide national level estimates of ED utilization by SCD patients, which have not previously been available.