Suppose you had a contact group called 'Prospects' which you wanted to further categorise into prospects to which you planned to send a prospective letter. Having two separate unconnected contact groups: 'Prospects' and 'Prospective Letter Contacts', for example, will not properly represent the structure that you intend. Instead, OfficeTalk lets you create a hierarchy of contact groups to properly represent the intended structure:
To make one contact group a sub group of another, do the following:
Create two top level contact groups, 'Contact Group 1' and 'Contact Group 2'.
Drag 'Contact Group 2' and drop it onto 'Contact Group 1'. 'Contact Group 2' will appear indented under 'Contact Group 1'. A button will appear to the left of 'Contact Group 1'. Pressing the button will hide the sub group. Pressing it again will show the sub group.
Note: Hierarchical contact groups still remain separate contact groups. This means that any companies or contacts belonging to a sub contact group will not inherently belong to the parent contact group.