Third party relationships in Workbooks are those which are between People and/or Organisations on your database rather than relationships that are directly with your Own Organisation.

Creating relationships between People

Open the Person tab on one of the People records for which you want to create the relationship and click Add Relationship.  Select the appropriate relationship type from the list that appears.  Search for the Person record that you want to relate to the original one.  Tick the checkbox next to the appropriate name and click Add.  (If the second person doesn't already exist on Workbooks, you can click New Person to create a record for them.)

Creating relationships between Organisations

Open the Organisations tab on one of the Organisation records for which you want to create a relationships and click Add Relationship.  Select the appropriate relationship type from the list that appears.  Search for the Organisation record that you want to relate to the original one.  Tick the checkbox next to the appropriate name and click Add.  (If the second organisation doesn't already exist on Workbooks you can click New Organisation to create a record for it.)

Creating relationships between People and Organisations

You can create these relationships by starting either with a Person or an Organisation record.  If you start with a Person record, open the Organisation tab and vice versa and click Add Relationship.  Select the appropriate relationship type from the list that appears.  Search for the record that you want to relate to the original one.  Tick the checkbox next to the appropriate name and click Add.