Bluetongue is a viral disease of cattle and sheep transmitted by Culicoides biting midges, which has recently emerged in Europe. This talk will describe the modelling work done at Pirbright to understand the spread and control of this disease, considering some of the pitfalls involved in using models to give policy advice when the models themselves are in the process of being developed. It will also present recent work in which the models were used to disentangle the roles of host movement and vector dispersal in transmission.