Business Process Model and Notation (BPMN) is the defacto standard for process modeling. However, BPMN is not truly meant to create business rules, statements that dictate what decisions should be made given a certain set of conditions. The new OMG standard Decision Model and Notation (DMN) 1.0 fills this gap in process modeling. DMN was designed as a graphical notation that models decisions and connects them to their related processes. With DMN, organizations finally have a standardized way to model and manage decisions and their business rules logic.
Decision modeling simplifies processes through the splitting of gateways and scripts into separate diagrams, thereby reducing the number of shapes and edges (lines). Decisions actually direct the flow of activities, allowing processes to respond dynamically to new business rules without the processes themselves changing. Process and decision diagrams have independent life cycles. Most business changes actually originate from the decision/rule level, so much can be achieved by focusing effort there.
Business rules are always evolving as a result of updates to best practices, regulatory changes, etc. This reality is reflected through decision modeling, allowing organizations to make consistent decisions and carry out end-to-end processes in the face of constant change.