There is growing controversy regarding illegal immigrants and their use of social services, including health care, in this country. We surveyed undocumented persons presenting at our emergency department to investigate the reasons why they sought care in the United States. Overall, 227 visits (8.6%) were made in the emergency department by illegal immigrants, mostly Hispanics. Of 104 patients surveyed, all sought care in this country because they were here at the time, and 86 (83%) intended to remain permanently. Of the 104 persons, 83 (80%) cited lack of funding as a reason for seeking emergency department care. Undocumented Hispanics had a higher uninsured rate (64%) than both Hispanics (32%) and non-Hispanics (30%). Of the 104 patients, 38 (36%) had difficulty obtaining care elsewhere because of their status, 53 (51%) knew of no other sources of care, and 46 (44%) said that even if available, only the emergency department was acceptable. Many undocumented persons seek care in the United States because they reside here permanently, often using this emergency department as their source of care. These findings may be important in light of recent efforts to restrict services for this group.