There has been a growing interest across the British conservation community in recent years in establishing conservation over large areas. Much of this thinking was crystallised in the Making Space for Nature report (Lawton and others 2010) , and has since become prominent in conservation policy. To maximise the success of future projects, there is a need to get a better overview of the many large-scale conservation (LSC) initiatives that already exist, and to investigate what can be learned from past experience. To date there has been no thorough study of the scope, spatial extent, management and planning approaches and effectiveness of LSC. This report summarises the results of a research study that provides the first comprehensive review of large-scale conservation initiatives in England, Scotland and Wales. The study was made up of a series of linked research projects with funding and support from Defra, Natural England, Scottish Natural Heritage and Natural Resources Wales and was carried out by the University of Southampton, University of Cambridge, Natural England and Atkins.