Our ability to diagnose, treat, and prevent HIV infection in pregnant women and in children has changed dramatically over the last few years. Recent developments include "early diagnostic" techniques such as polymerase chain reaction, quantitative viral load measurements to assist in estimating disease status and prognosis, newer antiretroviral therapies (including combinations) and effective antibiotic prophylaxis for HIV-infected children, and a better understanding of maternal-fetal factors that may mediate transmission of HIV. As children with long-term immunosuppression live longer, we are diagnosing new diseases and unusual clinical manifestations of common diseases. Children are living into their teenage years with perinatally acquired HIV infection, and we now find ourselves dealing with many of the complex medical and psychosocial issues that have confronted clients with other chronic diseases (e.g., diabetes, cancer): issues of growth failure; nutrition; depression' disclosure of illness to school, friends, and family; and death and dying. What separates HIV from other chronic diseases is its ability to infect and affect so many other family members, not just the child.