Operational Design
Operational design is the analytical framework that underpins operational-level planning: it helps commanders and staffs frame the operational environment, define the problem, and develop an operational approach [jointchiefs2011jp5].
A concise way to hold operational design is: before you schedule actions, you decide what system you are in, what must change in it, and what broad logic will make it change.
References
[jointchiefs2011jp5] Joint Chiefs of Staff. (2011). Joint Operation Planning. Joint Publication 5-0 (11 Aug 2011).
[nato2019ajp5] NATO Standardization Office. (2019). Allied Joint Doctrine for the Planning of Operations. Allied Joint Publication AJP-5 (Edition A, Version 2; 24 May 2019; STANAG 2526).
[usarmy2015atp5_0_1] Department of the Army. (2015). Army Design Methodology. Army Techniques Publication 5-0.1 (1 Jul 2015).
[usarmy2019adp5_0] Department of the Army. (2019). The Operations Process. Army Doctrine Publication 5-0 (31 Jul 2019).
[usmc2020mcwp5_10] United States Marine Corps. (2020). Marine Corps Planning Process. MCWP 5-10 (10 Aug 2020; Change 1, 30 Jan 2026).