Optimising HIV spending in eastern Europe and central Asia.

Competing Interests: We declare no competing interests. GM-R's institution receives funding from the Bill & Melinda Gates Foundation, FIND, and the US Agency for International Development. JWI-E's institution receives funding from the Gates Foundation, UNAIDS, and the US National Institutes of Health, and has received consulting fees from BAO Systems and support to attend meetings from UNAIDS, the Gates Foundation, the International AIDS Society, and the South African Centre for Epidemiological Modelling and Analysis.