The described arrangements and procedures provide a directory schema with object classes that have flexible attributes. This means that attributes can be extended independent of modifications to the directory schema. Specifically, an object instance of a content class described in the directory schema is instantiated. The content class includes a flexible attribute having a data type. A property is assigned to the attribute. The property is any combination of an operational and data providing property. The property is independent of the attribute's data type. Thus, without modifying the directory schema, multiple instances of the same object class can have attributes that provide completely different data types and completely different data operations.