Identifying persons with human immunodeficiency virus (HIV) infection who are unaware of their infection status, linking them to HIV care, and reducing racial/ethnic disparities are important national HIV prevention goals (1). Blacks/African Americans (blacks)* are disproportionately affected by HIV infection in the United States. Although blacks represent 13% of the U.S. population (2), in 2017, 44% of diagnoses of HIV infection were in blacks, and the rate of new diagnoses in blacks (41.1 per 100,000 persons) was approximately eight times that of non-Hispanic whites (5.1) (3). HIV partner services are offered by health officials to persons with diagnosed HIV infection (index patients) and their sex- or needle-sharing partners, who are notified of their potential HIV exposure and offered HIV testing and related services (4). CDC analyzed 2016 data from the National HIV Prevention Program Monitoring and Evaluation system submitted by 59 health departments.† Among 49,266 index patients identified as potential candidates for partner services, 21,191 (43%) were black. The percentage of black index patients interviewed for partner services (76%) was higher than that for all index patients combined (73%). Among the 11,088 black partners named by index patients, 78% were notified of their potential HIV exposure. Fewer than half (47%) of those notified were tested for HIV infection. Among those tested, one in six (17%) received a new HIV diagnosis. The prevalence of newly diagnosed HIV infection was particularly high among black partners who were gay, bisexual, and other men who have sex with men (MSM) (37%) and transgender persons (38%). Effective implementation of partner services is important to identify HIV infection, link patients to care or reengage them in care, and provide prevention services to reduce HIV transmission.