This paper is a summary of a three-year research project looking into when the option of giving people money instead of, or as well as, in-kind assistance is feasible and appropriate. A strong body of evidence is starting to emerge to indicate that providing people with cash or vouchers works. It is possible to target and distribute cash safely, and people spend money sensibly on basic essentials and on rebuilding livelihoods. What is more, cash transfers can provide a stimulus to local economies, and in some contexts can be more cost-effective than commodity-based alternatives. The paper concludes that giving people cash to enable them to buy what they need should be a staple part of humanitarian response and that humanitarian actors need to develop the skills to assess whether cash-based responses are appropriate, and to implement them when they are.