OR applied to humanitarian operations

The humanitarian caseload is growing rapidly while funds are declining. The sector clearly will have to do more with less. Optimizing constrained resources is the strength of OR. Our discipline can strongly support humanitarian practitioners provided it works on pressing real problems and translates its research into easily implementable tools whose effectiveness can be verified. This Special Issue gathers a very rich and varied collection of papers along those principles. It clearly shows the value of OR and the many exciting research problems in this important area of humanitarian operations.