Finding the financial means to achieve global health targets poses a huge challenge. Government donations can take years or even decades after formal approval to actually arrive. To overcome this hurdle and quickly raise huge sums for child vaccination programs, the International Finance Facility for Immunisation (IFFIm, pronounced 'if im') raises funds from private investors by offering them bonds backed by government pledges. Alan Gillespie, chairman of the board at IFFIm, interfaces between the source of the funds, the capital markets and the distributor, the Global Alliance for Vaccines and Immunization (The GAVI Alliance). Guided by Gillespie, IFFIm has thus far raised over $1 billion for vaccines, which is already flowing through GAVI into childhood immunization programs. Gillespie, who also serves as chairman of the Ulster Bank Group in Belfast, explains IFFIm's unique funding approach to Genevive Bjorn.