1-69. At the heart of the Army’s operational concept is decisive action. Decisive action is the continuous, simultaneous combinations of offensive, defensive, and stability or defense support of civil authorities tasks (ADRP 3-0). During large-scale combat operations, commanders describe the combinations of offensive, defensive, and stability tasks in the concept of operations. As a single, unifying idea, decisive action provides direction for an entire operation. Based on a specific idea of how to accomplish the mission, commanders and staffs refine the concept of operations during planning and determine the proper allocation of resources and tasks. They adjust the allocation of resources and tasks to specific units throughout an operation, as subordinates develop the situation or conditions change.