The Centers for Disease Control and Prevention (CDC) recently released revised recommendations for HIV testing in health care settings, calling for the performance of nontargeted opt-out HIV screening, the integration of informed consent for HIV testing into the general consent for medical care, and the uncoupling of prevention counseling and testing. It is unclear, however, whether patients will understand opt-out screening or be satisfied with integration of the consent for HIV testing into the general medical consent or the uncoupling of counseling from testing. The objective of this study is to evaluate patients' acceptance of the CDC's revised recommendations in an urban emergency department (ED). This was a cross-sectional survey study performed in the ED of an urban, public safety net hospital. The approximate annual ED census is 55,000 patients, and an approximate undiagnosed HIV seroprevalence ranges from 0.7% to 2.2%. A standardized survey instrument was developed and piloted and was then implemented with trained research assistants. Adult patients who were awake, alert, and agreed to participate in the study were included. During the 3-month study period, 529 patients were enrolled. The median age was 38 years (interquartile range 27 to 49 years; range 18 to 87 years), 57% were men, 48% were white, 28% were Hispanic, 18% were black, and 6% represented another race or ethnicity. When patients were asked whether they would have been tested had opt-out methodology been used, 81% (95% confidence interval [CI] 77% to 84%) would have agreed to be tested. When asked whether they would have been tested had opt-in methodology been used, there was no difference (absolute difference 0%; 95% CI -5% to 4%). However, explanation of opt-out screening was required for 11% (95% CI 8% to 14%), whereas explanation of opt-in screening was required for only 2% (95% CI 1% to 4%) (absolute difference 9%; 95% CI 5% to 11%). When asked whether the patient's physician recommended an HIV test during the ED visit, 93% (95% CI 91% to 95%) would have agreed to be tested. When asked whether consent for HIV testing should be separate from consent for general emergency medical care, 50% (95% CI 46% to 54%) agreed. When asked whether counseling was necessary before performing an HIV test, 34% (95% CI 30% to 38%) agreed, and when asked whether counseling was necessary after receiving a negative HIV test result, 35% (95% CI 31% to 40%) agreed. A large proportion of ED patients appear willing to be screened for HIV infection in accordance with the CDC's revised recommendations for HIV testing in health care settings. Similar proportions were willing to be tested when opt-out or opt-in screening strategies were used; however, a significantly greater proportion required explanation of opt-out screening.