In some situations, Relationships may be Mutually Exclusive, i.e. either one or other Relationship may be present, but not both.

For example, a particular SERVICE REQUEST may relate to either a CARE PROFESSIONAL ORGANISATION or a SERVICE POINT not both at the same time.

This 'either/or' situation is shown by a line spanning the Relationships in question.

An example of Mutually Exclusive Relationships in diagrams is given below: