A process model is a methodic graphical model used to show the sequential flow of a process. It describes the flow of work across certain tasks in an organization, system or program.
A process model can be as simple or as complex as necessary but it should be designed in a way that clarifies the process to the stakeholders.
Process models can be used to:
- Describe the solution or part of the solution.
- Describe the current state or future state of the process.
- Provide a clear description of the order of tasks or activities.
- Provide a visual representation to support a textual description.
- Provide a foundation for process analysis.
The business analyst can use a process model to describe the current state or as-is model of a process or the possible future state or to-be model.
A current state model is used to understand what is currently happening in the organization while the future state model shows the potential future state of the organization after the change has been implemented.
Process models usually include the following elements:
- The participants or actors in the process.
- The business event that triggers the process.
- All the steps or activities of the process.
- The paths or flows and decision points that logically connect those activities.
- The results of the process.
The most basic process model includes the following elements: a trigger event, a sequence of activities, and a result.
A more complete process model can include other elements, such as data, inputs and outputs, and descriptions that support the graphical representation.
Process models have numerous types of process models and these include:
1. Types of process models and notations: Various notations are used in process modelling, but the most commonly used notations include the following:
• Flowcharts and Value Stream Mapping (VSM): these are used in the business domain.
• Data Flow diagrams and Unified Modelling Language™ (UML®)
diagrams: these are used in the information technology domain.
• Business Process Model and Notation (BPMN): these are used in both
business and information technology domains and are could be considered as an industry standard.
• Integrated DEFinition (IDEF) notation and Input, Guide, Output,
Enabler (IGOE) diagrams: these are used for establishing scope.
• SIPOC and Value Stream Analysis: these are used for process modelling.
Process models usually have some or all of the following key components:
- Activity: this is a bit of work that forms part of the business process. It could be a single task or numerous sub-tasks.
- Event: this is an occurrence which starts, interrupts, or ends a task within a process or the process itself. It could be a message received, the passing of time, or a condition that is defined in the business rules.
- Directional Flow: this is a path that shows the logical order of the workflow. The diagrams are drawn to show the passage of time in a orderly manner such as from left to right.
- Decision Point: this is a point in the process where the work flow splits into two or more paths, which may be connected replacements or disconnected independent paths. The decision point is usually based on some business rules.
- Link: this is a connection between two or more process maps.
- Role: This is a person or group of people who are involved in the process. The descriptions usually match their job roles in the organizational model.
Flowchart: A Flowchart is a visual diagram that is used to describe an end-to-end process. They are a good way of understanding the process and explaining it to the stakeholders so that there is no confusion.
A flowchart can be simple, showing just a sequence of activities, or it can be more complex and include swim lanes.
A swimlane is a sectioned area that separates the activities in the process based on the user role. Swimlanes can be drawn both vertically or horizontally depending on the business analyst’s personal preference.
Pools are groups of swimlanes used to distinguish organizations and show interactions between two or more organizations.
Swimlanes are part of a pool, a pool may include a number of swimlanes, each of which represents a user role.
Business Process Model and Notation (BPMN): A Business Process Model and Notation (BPMN) is an industry-standard language used for model business processes in a format that both stakeholders and technical developers can understand.
BPMN uses swimlanes to differentiate the activities of the different
actors in a process.
When the workflow crosses the boundary of a swimlane, the responsibility for the task then passes to another role within the organization.
A process usually includes one pool for the customer and a second pool
for the organization.
Activity Diagram: The activity diagram is one of the use case diagrams described in the Unified Modelling Language™ (UML®).
Initially designed to add more details to a single use case, the activity diagram has been embraced for more universal process modelling purposes, including business process modelling.
While similar in appearance to a flowchart, the activity diagram typically employs swimlanes to show responsibilities, synchronization bars to show parallel processing, and multiple exit decision points.
Process modelling has its strengths and limitations, which include:
• Most stakeholders can easily understand a process when a process model is used
• It can be as simple or as complex as it needs to be, so it can be used to show the various perspectives of different stakeholder groups.
• It can be used to show different scenarios and parallel branches.
• It helps identify possible improvements by showing pain points in the process such as bottlenecks.
• It can form part of the business analysis documentation and can also be used in end user trainings.
• It provides clarity to stakeholders on the process responsibilities, sequence and hand-overs.
• It can be tedious and time consuming to prepare.
• It can become very complex and difficult to understand especially with complicated processes.
• It requires the stakeholders agreement on the process as shown in the process model.
• Not all process problems can be shown on the process model, so it might be necessary to support the model with textual descriptions.
• The process models need to be regularly maintained to ensure that they remain valid.