Scenario Development Phase 3 - Develop

Scenario Development | Phase 3 – Develop

The purpose of the develop phase is to provide a compilation of products that set the initial conditions and timeline of events imposed on the training audience. Within the scenario, the training audience is presented with problems, completes tasks, and makes decisions to achieve training outcomes. Although the resolution of a scenario can vary greatly, it always addresses the operational environment and general situation.

Events are usually scenario-supported whereas exercises are often scenario-driven.

  • Scenario-supported. In a scenario-supported event, the scenario provides a realistic backdrop for the unit to accomplish its primary goal but does not drive the outcome. 
  • Scenario-driven. In a scenario-driven exercise, the scenario drives unit decision-making and accomplishment of its outcomes. The scenario design prompts the actions of the training audience.

Effective decision making requires both situational understanding to recognize the essence of a give problem and the creative ability to devise practical solutions. The scenario focuses on providing varying degrees of fidelity and resolution to the training audience. It creates the operational environment and constructed situation that are relevant to the scope of the event or exercise being designed.​

The scenario is a compilation of products that set the initial conditions and timeline of events imposed on the training audience. Within the scenario, the training audience is presented with problems, completes tasks, and makes decisions to achieve training outcomes. Although the resolution of a scenario can vary greatly, it always addresses the operational environment and general situation.​

The developer must define the operational environment in relation to the event or exercise. The definition of the operational environment (OE) describes the operational variables that frame an event or exercise.

The operational environment is defined as a composite of the conditions, circumstances, and influences that affect the employment of capabilities and bear on the decisions of the commander. 

The major decision that needs to be made is whether the training OE will be based on an actual OE or a composite Decisive Action Training Environment (DATE) OE. This decision depends on whether the event or exercise is based on a directed or contingency mission. If a unit is assigned a contingency mission in a particular area of the world, its training could be based on a real location and OE. If a unit is focused on executing its mission essential tasks, the OE could be selected from one of the DATE countries located on the OE Data Integration Network (ODIN).

Success in MDO and LSCO requires a complex and dynamic OE (with a mixture of well-structured and ill-structured problem sets) to challenge leaders and service members across the continuum of competition, crisis, and armed conflict in all warfighting functions.

For a scenario to be considered compliant (actual or composite), it must replicate the complex and interrelated Operational Variables for the type of event or exercise and IAW senior Army directives, exercise director’s guidance, and training objectives and outcomes.

The construction of an operational environment may range from a simple situation paragraph to a complex country fact book, depending on the training objectives. These operational variables, referred to as PMESII-PT (Political, Military, Economic, Social, Information, Infrastructure, Physical Environment, and Time), describe conditions, both military and nonmilitary, of an operational area that gives commanders and staffs fundamental situational understanding before engagement. Analysis of the PMESII-PT variables will help commanders and staffs at all levels understand their OEs and facilitate a common operational picture of its complexities.

The following is a brief description of each PMESII-PT variable, along with examples (in parentheses) of questions a commander might need to have answered about each variable in this particular OE:​​

Political: Describes the distribution of responsibility and power at all levels of governance—formally constituted authorities, as well as informal or covert political powers. (What are the strategic objectives of each country?)

Military: Explores the military and/or paramilitary capabilities of all relevant actors (enemy, friendly, and neutral) in each OE. (What is the force structure of the enemy?)

Economic: Encompasses individual and group behaviors related to producing, distributing, and consuming resources. (What is the unemployment rate?)

Social: Describes the cultural, religious, and ethnic makeup within an OE and the beliefs, values, customs, and behaviors of society members. (What is the ethnic composition of the OE?)​​

Information: Explains the nature, scope, characteristics, and effects of individuals, organizations, and systems that collect, process, disseminate, or act on information. (How much access does the local population have to news media or the internet?)​​

Infrastructure: Details the composition of the basic facilities, services, and installations needed for the functioning of a community or society in the OE. (What are the key modes of transportation?)​​

Physical Environment: Depicts the geography and man-made structures as well as the climate and weather in the OE. (What types of terrain or weather conditions in this area of operations favor enemy operations?)

 Time: Describes the timing and duration of activities, events, or conditions within an OE, as well how the timing and duration are perceived by the various actors in the OE. (What is the cultural perception of time in this OE?)


The general situation is an initial set of conditions and timeline of significant events imposed on the training audience to achieve the training objectives. It gives the training audience the background information typically available in a combat situation, including events leading up to the point of execution and information necessary to place the training audience in the tactical setting.

The general situation, often called the “road to war” or “road to crisis,” is information that provides the training event or exercise start data necessary to place the training audience within the appropriate conditions to execute specific training objectives. This is typically a narrative utilizing the operational environment as contextual background.



At their core, storylines are tools used to construct and sequence scenario event stimulation (e.g., scripts, OPFOR guidance, forcing functions etc.), often called injects. They document scenario event problems through a series of observable indications and warnings meant to drive the training audience to decide and act in a predictable manner. 

A storyline generally consists of three sections: 

  • Descriptive Information. 
  • Scenario Event Stimulation. 
  • Production Requirements



Descriptive information is the first section of a storyline. It is the information that describes the storyline and to supports the aggregation of a MSEL during the development phase. Examples of descriptive information follow.

Thread Begin/Thread End. The date and time the first and last injects are introduced. 

Purpose. A description of why a storyline is being designed. It outlines the main reason for the storyline. It is associated with achieving a main training action or event. 

Description. A narrative describing how the storyline will be implemented. It outlines the sequence of injects and actions being conducted. The description ends with a statement of the expected action on the part of the training audience. 

Method of Implementation. A list of inject platforms required to introduce each inject to the training audience. 

Required Coordination. A list of who and what needs to be coordinated to construct and implement each inject. 

Target Audience(s). Units or individuals that will perform actions in response to the storyline. 

Assumptions. A list of presumed circumstances that must be confirmed as being true in order for the storyline to be effective.


The second section of the storyline focuses on identifying and sequencing stimulation. Scenario event stimulation is any data, information, or scripted action designed to be introduced to the training audience for one of the following reasons:​​

  • Stimulation Identification. Scenario events generally require multiple types and forms of stimuli to elicit a single action or behavior on the part of the training audience. The first step in completing the second section of a storyline is identifying each stimulating event.

A technique often used to identify stimulus for a scenario event is to ask the question, “What type(s) of stimulation would the training audience need to receive to act in a manner that would allow a behavior that is described in the scenario event objective to be observable?”

Once the stimulus is identified, the designer considers the scenario and operational environment to ensure the training audience will perceive the stimulus as being logical. Stimulus presented to the training audience must originate from somewhere. The following are sources of event or exercise stimulation:

  • Live Actions ​
  • Virtual Simulation ​
  • Constructive Simulation​​
  • Live Actions. Live action applies to individual Soldiers or units in the training audience using their actual equipment in real-world conditions responding to guided, unscripted reactions of training enablers. Live actions are guided by the restraints and constraints of the scenario and the controlling agency. 
  • Virtual Simulation. Virtual simulation involves individual Soldiers or units training with simulated elements of the operational environment or their organizational equipment (virtual entities). Virtual simulation includes either deliberate or dynamic scripted actions. Deliberate scripting applies to development of preplanned actions executed in accordance with the MSEL. Dynamic scripting applies to rapid development of unplanned actions executed in accordance with control element guidance.
  • Constructive Simulation. Constructive simulations create entire units, staffs, or capabilities so a training audience can train as if they were interacting with real units and/or support capabilities against and OPFOR through a simulation. 


The order in which stimulation is presented to the training audience has an important role in ensuring the training audience decides and acts toward a specific behavior. For this reason, the second step in completing this section of a storyline is to chain or sequence related stimulation. This can be accomplished by using a fishbone diagram to both identify the basic information about and the sequence in which each associated inject should be presented to the training audience.​

SD StimSeq

The diagram should include— 

  • An inject number. ​
  • A date/time group the inject should be introduced. ​
  • A description of the inject or actions. ​
  • A description of the training audience’s expected actions.

Before the developer can transition to the detailed development of events and exercises, the scenario and storylines must be approved by the exercise director.


During drafting of the scenario concept, the development team identifies necessary scenario event stimuli to achieve each training objective. The MSEL is a consolidation of all scenario event stimuli in a specific sequence to ensure all training objectives are accomplished. It contains stimuli designed to maintain the exercise sequence and prevent unintended tangents. The MSEL is an execution tool that documents essential elements of scenario events. It is the primary device for exercise and scenario management.

While there is no standardized format for a MSEL, there are common elements found on most MSELs. These elements allow control personnel and implementers to quickly and accurately manage the presentation of scenario events and other stimulus to the training audience.

  • Line Number
  • Date and Time
  • Storyline Name
  • Scenario Event Identifier
  • Inject Number
  • Description
  • Target Audience
  • Inject Platform
  • Remarks

Line Number. Injects are numbered after they are aggregated on a MSEL and sequenced in order of delivery date and time. The number is identified as the MSEL line number and is utilized to identify MSEL inject lines. ​

Date and Time. The date and time an inject is meant to be introduced into the scenario. This is transferred to the MSEL from the storyline. ​

Storyline Name. The storyline that the inject was designed to support. This is transferred to the MSEL from the storyline. ​

Scenario Event Identifier. The scenario event the inject was designed to support. This is transferred to the MSEL from the storyline. ​

Inject Number. With the scenario event identifier, inject number identifies the sequence of specific scenario event injects. This is transferred to the MSEL from the storyline. ​

Description. A brief synopsis of the inject. ​

Target Audience. Identifies who within the training audience should decide and act on the inject. ​

Inject Platform. Identifies who or what will first report or observe the inject. ​

Remarks. Any special comments or remarks the control element should be aware of when introducing the inject. It often provides supporting information to prepare for RFIs or dynamic development. ​


Although all events and exercises have control functions that must occur within them, the size and capability of the control element will vary based on the type of event or exercise and the size of the training audience. 

Control Element Functions. While control elements (e.g., exercise control or site controllers) often have numerous tasks to perform, all control organizations must execute the following three core functions:

Model the Learning Environment. Modeling the learning environment is the act of logically representing the conditions that will be performed. This requires the control element to safely replicate the environment and conditions associated with the competition continuum. The learning environment should be learner centric and adaptable.

Manage the Presentation of Stimulation. The decision to present scenario events or stimulation to the training audience must be made or approved by a single individual within the control element. The individual making these decisions must have a clear understanding of— 

  • The current operational environment status. 
  • The training audience’s perception of the current situation. 
  • Training objectives yet to be accomplished and the planned course to achieve them.

Observe and Measure Behavior. It is essential that decisions made by the training audience and resulting actions are observed and measured during execution. 

​Control Tasks :​

• Manage the conduct of scenario events in accordance with the training schedule. ​

• Manage the execution of the MSEL. ​

• Manage risk and ensure training audience safety. ​

• Stimulate and influence the training audience to take actions that align with the training objectives. ​

• Coordinate and direct the training audience evaluation. ​

• Adjudicate the outcome of engagements between friendly and enemy forces. ​

• Coordinate the activities of the OPFOR. ​

• Manage response cells. ​

• Inform the exercise director of significant events, incidents, issues, and training audience future intentions. ​

• Coordinate, direct, and control support and enabler resource employment. ​

• Coordinate with and control all external activities that are participating in or supporting the event or exercise.​


The stimulation development requirements list is the third section of a storyline. This list associates stimulations depicted on the timeline with individuals or working groups to develop them during the next phase of the scenario development process.​

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