# Logical Data Modeling - Relationship Direction (Directed/Undirected)

The direction of a relationship shows if the relationship can be interpreted in one or both directions.

There is only two options:

## Type

### Directed

A directed relationship models asymmetric relations (ie the relationship can be interpreted in only one direction)

It represents a Relationship between a collection of source model elements and a collection of target model elements. A Directed Relationship is said to be directed from the source elements to the target elements.

### Undirected

An Undirected relationship models a symmetric relations (ie the relationship can be interpreted in both directions)

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