Dunning notices are generally created per business partner. In special cases, it can be useful to group together the open items of a business partner according to certain aspects and dun these items together.
In order to group items together for dunning notices, you need to define grouping keys (two-character, alphanumeric). For each key, specify a field from the line item whose contents are to comprise the main criteria for the group. Items whose contents in this field are identical, are dunned together.
You are using the Financial Assets Management system and want to send your business partner a separate dunning notice for each leased property. To do this, you define a grouping key referring to the contract number field. As a result, open items with the same contract number can be dunned together.