 This study found that the technical efficiency of HIV aid spending has improved over time, but there is still room for improvement. Countries that are more efficient in converting their spending into outputs include those in Europe and Eastern and Southern Africa. These countries have seen the greatest improvements in efficiency since 2010. Additionally, countries with higher gross national income, human development index, lower HIV prevalence, and lower out-of-pocket expenses tend to be more efficient. This article was authored by Kasim Malal, Gerard Joseph Abu Joud, Charles Byrenji, and others.