What principle of sustainment addresses reacting to changing requirements?

The principle of sustainment that focuses on reacting to changing requirements is responsiveness. This concept emphasizes the ability to swiftly and effectively adjust resources, plans, and operations to meet evolving needs or circumstances. In practice, responsiveness ensures that a system can adapt without significant delays or disruptions, allowing for continuous support and maintaining operational effectiveness.

Being responsive is critical in environments where conditions can change rapidly, such as military operations or emergency response scenarios, where the ability to reassess and realign resources is essential for success. This principle directly correlates with maintaining momentum and ensuring that support meets the dynamic demands of the situation.

Other principles like improvisation and anticipation play significant roles in planning and executing operations, but they do not specifically highlight the immediate reaction to changes in requirements as effectively as responsiveness does. The principle of economy, meanwhile, emphasizes efficiency in resource use rather than reaction to change.