BPMN Essentials: Notation, Concepts, and Practical Examples

Business Process Model and Notation (BPMN) is a standardized graphical representation used for specifying business processes in a workflow. It provides a visual language that is intuitive for business users and detailed enough for technical developers to implement. Below is a comprehensive guide to BPMN, including notation summary, key concepts, and examples.

Notation Summary

BPMN uses a variety of symbols to represent different elements of a business process. Here’s a summary of the key symbols:

Participants

• Pool: Represents major participants in a process, often an entire organization or department.
• Lane: A sub-partition within a pool, typically representing a role or department within the organization.

Artifacts

• Text Annotation: Provides additional information about the process.
• Group: A visual grouping of activities, often used to highlight a specific part of the process.

Gateways

• Exclusive: Represents a decision point where only one path is chosen.
• Inclusive: Allows multiple paths to be taken simultaneously.
• Parallel: Splits the process into parallel paths that are executed concurrently.
• Event: Triggers a process or subprocess based on an event.

Data

• Data Object: Represents information flowing through the process.
• Data Store: A place where data can be read from or written to.

Activities

• Task: A single unit of work.
• Subprocess: A process within a process, can be collapsed or expanded.
• Call Activity: Invokes another process or subprocess.
• Event Subprocess: A subprocess triggered by an event.
• Transaction: A subprocess that must be completed in its entirety or not at all.

Key Concepts

1. Process: A collection of related activities that produce a specific outcome.
2. Flow Objects: The main elements that define the behavior of a process (Events, Activities, Gateways).
3. Connecting Objects: Used to connect flow objects (Sequence Flow, Message Flow, Associations).
4. Swimlanes: Used to organize and categorize activities into pools and lanes.
5. Artifacts: Provide additional information about the process but do not affect the flow.

Examples

This diagram is a Business Process Model and Notation (BPMN) diagram that illustrates a purchase order process. Here’s a detailed explanation and interpretation of the diagram:

Key Components:

1. Pools and Lanes:

   • Pools: Represent major participants in a process. In this diagram, there are two pools: the “Customer” and the “Drinks Shop.”
   • Lanes: Subdivisions within a pool that represent different roles or departments. Here, the “Drinks Shop” pool is divided into two lanes: “Sales Representative” and “Warehouse.”

2. Message Flow:

   • Indicated by dashed red lines, message flows show the exchange of messages between different pools.
   • The customer sends a “Purchase Order” to the Drinks Shop and later receives an “Invoice.”

3. Tasks:

   • Represented by rounded rectangles, tasks are activities performed within the process.
   • Check Stock Level: The sales representative checks the stock level upon receiving the order.
   • Suggest Change: If the stock is insufficient, the sales representative suggests changes to the purchase order.
   • Request Pack Goods: If the stock is sufficient, the sales representative requests the warehouse to pack the goods.
   • Pack Goods: The warehouse packs the goods.
   • Ship Goods: The warehouse ships the goods, completing the order.

4. Gateway:

   • Represented by a diamond shape, a gateway controls the flow of the process based on conditions.
   • Sufficient Stock?: This gateway determines whether there is sufficient stock to fulfill the order. If yes, the process flows to “Request Pack Goods”; if no, it flows to “Suggest Change.”

5. Events:

   • Message Start Event: Indicated by a circle with an envelope icon, this event triggers the start of the process when a message (purchase order) is received.
   • End Event: Indicated by a circle with a thick border, this event marks the completion of the process.

6. Sequence Flow:

   • Indicated by solid arrows, sequence flows show the order of activities within the process.
   • The sequence flow starts from the “Order received” event, moves through the tasks and gateway, and ends at the “Order Completed” event.

Process Flow:

1. Order Received:

   • The process begins when the sales representative receives a purchase order from the customer.

2. Check Stock Level:

   • The sales representative checks the stock level to determine if the order can be fulfilled.

3. Gateway (Sufficient Stock?):

   • If the stock is sufficient, the process moves to “Request Pack Goods.”
   • If the stock is insufficient, the process moves to “Suggest Change,” where the sales representative suggests changes to the purchase order.

4. Request Pack Goods:

   • If the stock is sufficient, the sales representative requests the warehouse to pack the goods.

5. Pack Goods:

   • The warehouse packs the goods as requested.

6. Ship Goods:

   • The warehouse ships the goods to the customer.

7. Order Completed:

   • The process ends with the order being completed and an invoice being sent to the customer.

Interpretation:

This BPMN diagram provides a clear visual representation of the purchase order process, highlighting the interactions between the customer and the drinks shop, as well as the internal activities within the shop. It helps in understanding the flow of activities, decision points, and the roles involved in fulfilling a purchase order. This diagram can be used for process improvement, training, and ensuring that all stakeholders have a common understanding of the process.

Best Practices

1. Clarity: Ensure the diagram is clear and easy to understand.
2. Consistency: Use symbols consistently across different diagrams.
3. Documentation: Use text annotations to provide additional context where necessary.
4. Modularity: Break down complex processes into manageable subprocesses.
5. Validation: Regularly validate the process model with stakeholders to ensure accuracy.

By following this guide, you can effectively model business processes using BPMN, ensuring clear communication and efficient process management.

BPMN References