Sustainable livelihoods (SL) is a way of thinking about the objectives, scope and priorities for development, in order to enhance progress in poverty elimination. SL approaches rest on core principles that stress people-centred, responsive, and multi-level approaches to development. Although SL approaches are relatively new within DFID, they have already been applied in a variety of ways. Both new and existing development activities have used SL approaches to focus more clearly on the priorities of the poor. The approaches have been applied flexibly, in contexts ranging from project and programme preparation, to research and sub-sector reform.