Genome sequencing can be used to discover new pathogens but it can also be used to monitor known ones. This is known as genomic surveillance and it becoming an increasingly important tool in the response to viral outbreaks. We have demonstrated that a portable laboratory for virus sequencing can be flown to the epicentre of an ongoing outbreak and provide rapid, actionable results from the field. This avoids the delays associated with shipping samples out the country for sequencing elsewhere. We have set up mobile labs in Guinea during the 2014 West African Ebola outbreak and to Brazil during the 2015 Zika outbreak. I will talk about what goes into building a mobile lab and the ways in which they can be of use in an ongoing outbreak.