The Pipeline and Hazardous Materials Safety Administration (PHMSA) and the Federal Aviation Administration (FAA) are alerting shippers and carriers to the importance of transporting lithium batteries safely. PHMSA and FAA are concerned that many persons who ship lithium batteries do not recognize the hazards posed by these batteries during transportation. We are issuing this advisory guidance to (1) Inform persons of recent aviation incidents involving fires aboard both passenger and cargo aircraft and the potential hazards that shipments of lithium batteries may present while in transportation, (2) provide information concerning the current requirements for the transportation of lithium batteries and (3) inform persons of the actions we have taken to date and plan to take in the future to address the hazards of these batteries.