HIC-Vac is an international network of researchers working together to grow and develop human infection challenge studies, with the goal of accelerating the development of vaccines against pathogens that have a high global impact. The aim is to reduce the burden of some of the world's most crippling diseases. While new vaccines are being brought to market every year there are still some major gaps that need to be addressed. And given the decline in the efficacy of antibiotics and the rise in antimicrobial resistance, a focus on new bacterial vaccines is becoming particularly urgent. HIC-Vac provides small awards to members who have developed a high quality research proposal to carry out preliminary work for new human challenge studies, or to add value to existing studies. One specific goal is to accelerate development of vaccines that are beneficial in low and middle income countries, where preventing disease will have the biggest impact. Human challenge studies can play an important role in accelerating vaccine development by providing a proof of principle that the vaccine has efficacy in a small group of participants. This can reduce the time and cost it takes to get an indication of whether a candidate vaccine has promise and should be pursued. But the wider benefits of human challenge studies must be weighed up against the ethical acceptability of experimentally exposing people to an infection. Research ethics committees in the UK are integral in ensuring that HIC-Vac supports projects that are ethical and give robust results that justify the model.