The 1994 International Conference on Population and Development (ICPD) established goals for the expansion of population assistance. To date, the financial promises made by donor countries in 1994 have not been met. To unravel the gap between ambitions and contributions, we use panel estimation methods to see what lies behind the level of donor contributions and the sharing of burdens across the various categories of population and HIV/AIDS assistance in 21 donor countries for the years 1996–2002. Contributions by donors depend heavily on the economic wealth and subjective preferences of donor countries. The sharing of the ICPD burden within the group of OECD/DAC countries is in line with the countries’ ability to pay, although within the aggregate we observe a specialization in channels for aid: small countries predominantly use multilateral aid agencies, whereas large countries rely more on bilateral aid channels. Catholic countries are averse to donating unrestricted funds (flowing primarily to multilateral agencies) or restricted funds targeted at family planning programs.