text: Chapter 2
  However, since some transitions may defy anticipation, leaders always design and prosecute operations with
  flexibility in mind. Maintaining reserves is one way of maintaining flexibility.
  2-29. Anticipating transitions and managing them effectively are a commander’s responsibility. When
  commanders anticipate a transition, they, their staffs, and subordinate leaders carefully consider these actions
  to ensure success:
  * Forecasting in advance when and how to transition.
  * Arranging tasks to facilitate transitions.
  * Creating a task organization that anticipates transitions.
  * Rehearsing certain transitions such as from defense to counterattack or from offense to
  consolidating gains.
  2-30. Forces are vulnerable during transitions, so commanders establish clear conditions for their execution.
  Commanders and staffs identify potential transitions and account for them throughout execution. Effective
  commanders consider the time required to plan for and execute transitions. Assessment helps commanders
  measure progress toward transitions and take appropriate actions to execute them. Each echelon has a
  responsibility to anticipate and facilitate transitions for subordinate echelons.
  Operational Reach
  2-31. While designing operations, it is critical to consider operational reach—the distance and duration
  across which a force can successfully employ military capabilities (JP 3-0). The limit of a unit’s operational
  reach is its culminating point. The concept of operational reach is inextricably tied to the concept of basing
  and lines of operations. Reach may be constrained by the geography, threats, and environmental conditions
  in and around an operational area. Reach may be extended through forward positioning of capabilities and
  resources, leveraging host nation and contracted support, and maximizing the throughput efficiency of the
  distribution system.
  2-32. Sustainment enables operational reach. Commanders and staffs increase operational reach through
  deliberate, focused operational design and appropriate sustainment resource allocation. This requires
  strategic sustainment capabilities such as materiel, supplies, health services, and other support and the global
  distribution systems to deploy, maintain, and conduct operations over great distances for extended periods.
  Army forces can increase the joint force’s ability to extend operational reach by securing and operating bases
  in the AOR, the use of contracted and local procurements, and the use of aerial delivery.