A uniform mechanism for building containment hierarchies separates the code/method which actually perform the containment insertion operations on the components from the specification of the containment and then provides an automatic way of obtaining and executing that code when containment hierarchies need to be created. The mechanism consists of an abstract syntax for describing the containment relationships, processing mechanism for creating the containment mechanism, and a registry containing the mechanisms for implementing specific containment policies. Having this abstraction allows an application programmer to be able to construct hierarchies of objects without having to be concerned about the specific details of how that containment is performed. In fact, the details may be deferred until run-time (and even downloaded from elsewhere). Also, having this abstraction significantly simplifies automatic generation of object hierarchy codes, both from the point of view its implementation as well as that of the code that is generated.