In this cross-sectional study, a community-based sample of 162 younger and older adults with and without HIV was compared on neuropsychological and everyday-functioning measures. In the HIV sample, the relationship between cognition, everyday functioning, and HIV biomarkers was also examined. A battery of cognitive tests was completed along with two laboratory measures of everyday functioning and one measure of HIV medication adherence. Main effects for age and HIV were found on several neuropsychological measures and on the Timed Instrumental Activities of Daily Living test; those who were older or who had HIV exhibited poorer performance. Although age-by-HIV interactions were not observed, older adults with HIV as a group performed worse on eight out of the nine neuropsychological and everyday functioning measures. Few of these neuropsychological and everyday measures were related to HIV biomarkers (e.g., CD4+ T cell count). Implications for nursing practice and research are posited. © 2013 Association of Nurses in AIDS Care.