Biodiversity is recognised to be of global importance, yet species and habitats continue to be under increasing pressure from human-induced influences. Environmental concerns are high on the political agenda, driving increased legislation to protect the natural environment. The starting point for much of this legislation is the requirement for a comprehensive biodiversity audit. For those needing to undertake such audits, this Handbook, first published in 2005, provides standard procedures which will enable practitioners to better monitor the condition of the biodiversity resource, resulting in improved data upon which to base future policy decisions and actions. Organised in three parts, the Handbook first addresses planning, covering method selection, experimental design, sampling strategy, and data analysis and evaluation. The second part describes survey, evaluation and monitoring methods for a broad range of habitats. Part three considers species and provides information on general methods before addressing specific methods of survey and monitoring for the major taxonomic groups.