This publication sets out the report of the inquiry by the five-member committee, chaired by Lord Butler, established in February 2004 to examine the quality of intelligence used as justification for UK military participation in the war against Iraq in March 2003. The inquiry's remit was to investigate discrepancies in the gathering, evaluation and use of intelligence on Iraqi weapons of mass destruction (WMDs). The report includes the September 2002 intelligence dossier, which alleged Iraq was capable of deploying WMD within 45 minutes. Given the subsequent failure by the Iraq Survey Group to find WMDs in Iraq, the report makes recommendations for future practice, in the light of the difficulties of operating in countries of concern. The report focuses structures, systems and processes rather than on the actions of individuals.