u Easy to implement
u normalized data model
u can use attributes
u relationships by reference
u Useful
u archiving
u import/export format
<company>
<emps>
<emp emp-no="4321"
     name="Bernhard Weichel"
     adress="stuttgart"/>
<emp emp-no="12345"
     name="Helmut Gengenbach"
     adress="schwieberdingen"/>
</emps>
<depts>
<dept name="K3/EES4" mgr="4321"/>
<dept name="FV/PLI" mgr="0815"/>
</dept>
</company>