An Operation Plan is any plan, except the SIOP, for the conduct of military operations in a hostile environment prepared by the commander of a unified or specified command in response to a requirement established by the joint chiefs of staff. Operation plans are prepared in either complete or concept format. An Operation Plan in Complete Format (OPLAN) is an operation plan for the conduct of joint operations that can be used as a basis for development of an OPORD. Complete plans include deployment/employment phases, as appropriate. An Operation Plan in Concept Format (CONPLAN) is an operation plan in an abbreviated format that would require considerable expansion or alteration to convert it into an OPLAN or OPORD.