The field of HIV medicine has changed rapidly in the last two decades since effective and tolerable antiretroviral treatment became available. As a result, although classical opportunistic infections of the brain have become less common, clinicians need to be aware of a wider range of acute and chronic complications of HIV and its treatment. In this article, we summarise major opportunistic infections, immune reconstitution inflammatory syndrome, HIVassociated neurocognitive disorders, and cerebrovascular disease in HIV positive patients. We also emphasise the preventability and reversibility of most of the central nervous system complications of HIV, and hence the importance of early diagnosis of HIV and involvement of clinicians with special expertise in HIV medicine.