Which process model notation can describe very complex lateral and parent-child relationships?

Unified Modeling Language (UML) is a versatile modeling notation that is particularly well-suited for representing complex relationships within a system, including lateral and parent-child associations. UML provides a standardized way to visualize the design of a system through various diagram types, such as class diagrams, sequence diagrams, and use case diagrams.

In UML, you can depict intricate relationships through associations, aggregations, and compositions, which allows for a clear representation of how different entities interact and relate to one another. For instance, a class diagram can show a parent-child hierarchy through inheritance, while associations can illustrate lateral relationships between different classes or objects.

This capability to model both hierarchical and relational structures is especially useful in software design and systems engineering, where understanding the interactions and dependencies among components is critical for effective design and implementation. Other models like flow charts and event-driven process chains may not accommodate the same level of complexity or detail in depicting such relationships.