3-5. Sustainment is inherently joint and requires a coordinated and collaborated effort between the Services, UAPs, and multinational partners. Sustainment determines the depth and duration of Army operations. It is essential to retaining and exploiting the initiative and it provides the support necessary to maintain operations until mission accomplishment. Failure to provide sustainment could cause a pause or culmination of an operation resulting in the loss of the initiative and failure to exploit tactical successes. It is essential that sustainment planners and operation planners work closely to synchronize all of the warfighting functions, in particular sustainment, to allow commanders the maximum flexibility to conduct decisive action.