PREFACE Doctrine consists of fundamental principles by which military forces guide their actions in support of objectives. It is authoritative but requires judgement in application. The planning@ execution and support of military operations require a clearly understood and widely accepted doctrine. This is especially important when combined@ multinational or coalition forces conduct operations. Joint doctrine applies when two or more components operate together. North Atlantic Treaty Organisation (NATO) military Information Operations (Info Ops) doctrine is intended primarily for use by NATO forces@ and provides a useful framework for operations conducted by a coalition of NATO partners@ non-NATO nations and other organisations. Interoperability between NATO nations is based upon NATO standardisation agreements and publications; many of the subjects covered in these may have to be reconsidered in the planning of Info Ops with non-NATO forces in accordance with North Atlantic Council (NAC) agreed decisions and procedures. This doctrine@ therefore@ provides a common baseline for achieving Info Ops interoperability@ rather than trying to encompass each nation's Info Ops approach. The purpose of Allied Joint Publication (AJP)-3.10 Allied Joint Doctrine for Information Operations is to explain how Info Ops support the planning@ conduct and assessment of operations. The provenance for AJP-3.10 is MC 422/3 NATO Military Policy on Information Operations@ which clearly acknowledges the primacy of civil/political direction on information issues and that the policy and subordinate doctrine applies to the military lever of power only. AJP-3.10 is focused on the operational level. It defines and discusses principles of Info Ops@ and highlights those particular Info Ops considerations relevant to the conduct of operations@ such as the sensitivity to political factors@ and the role of non-military entities and emerging technological capabilities in the information environment@ both within and external to NATO. The ongoing debate about the span of Info Ops has fuelled doctrine development based on real world necessity. AJP-3.10 must be seen as a living document@ centred on how Info Ops supports the Joint Force Commander's (JFC's) mission. AJP-3.10 is intended principally for use by a JFC@ Combined Joint Task Force (CJTF) commander@ Deployable Joint Task Force (DJTF) commander and those of their staff with Info Ops responsibilities. It addresses the roles@ links@ responsibilities and required products from the strategic@ operational and tactical commands. Each echelon of command will be responsible for developing specific Standing Operating Procedures (SOPs) to reflect Headquarters (HQ)/command specifics@ as appropriate. Within the overall NATO publication hierarchy@ AJP-3.10 is directly subordinate to AJP-3 Joint Operations@ which is one of NATO's keystone publications focused on staff functions. AJP-3 describes the fundamental operational aspects of joint operations and provides guidance on their conduct. Furthermore@ AJP-3.10 links directly to AJP-01 and the available policy documents containing Info Ops content.