A future fusion reactor will use deuterium and tritium as fuel. The former is found in abundance in seawater, while the latter is not available naturally due to its short lifetime. Present developments in the context of fusion propose generating tritium in a blanket based on the reaction n + Li-6 -> T + He. This paper will review the issue of the reserves and resources of lithium as the fuel for fusion energy. We describe the available reserves and resources and their chemical forms. We analyze the present production and consumption for industrial uses, completing this over-view by referring to a life cycle analysis in the case of the lithium production from brine. The lithium extraction from seawater is also described. Taking into account the previous data and the requirements estimated for fusion plants, we propose scenarios for future lithium consumption, and we conclude on the lithium availability over the next centuries dealing with the different hypothesis considered. (c) 2005 Elsevier B.V. All rights reserved.