According to the Disease Control Priorities Project, expanding vaccination is an excellent fit for donors who want proven, cost-effective, scalable ways of helping people. According to this table (more detailed version on page 401 of the full report), both South Asia and sub-Saharan Africa have relatively low levels of existing coverage (50-58%), and vaccinating more children could save lives for about $200 each. If saving lives is in fact your priority (and we know it isn’t for all donors), that’s hard to beat.

The most promising nonprofit I know for implementation is the GAVI Alliance, which we have yet to thoroughly evaluate.