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By enforcing a strict separation between interface and implementation and by making software architecture explicit, component-based programming can facilitate the implementation and maintenance of complex software systems.  Coupled with the use of meta-programming techniques, component-based programming can hide to application programmers some of the complexities inherent in the handling of non-functional aspects in a software system, such as distribution and fault-tolerance, as exemplified e.g. by the container concept in Enterprise Java Beans (EJB), CORBA Component Model (CCM), or Microsoft .Net.

Existing component-based frameworks and architecture description languages, however, provide only limited support for extension and adaptation.  This limitation has several important drawbacks:  it prevents the easy and possibly dynamic introduction of different control facilities for components such as non-functional aspects; it prevents application designers and programmers from making important trade-offs such as degree of configurability vs performance and space consumption; and it can make difficult the use of these frameworks and languages in different environments, including embedded systems.

The Fractal component model alleviates the above problems by introducing a notion of component endowed with an open set of control capabilities.  In other terms, components in Fractal are reflective, and their reflective capabilities are not fixed in the model but can be extended and adapted to fit the programmer's constraints and objectives.