A well-run organisation will generally have clearly defined goals, that are understood and pursued by directors, employees and other agents acting on the behalf of the organisation.

Enterprise Architecture as a discipline, has the responsibility to ensure that the use of resources (manpower, assets, money, etc.) is consistently and permanently aligned, at all levels of detail, with the needs of the enterprise.

More specifically, these needs are defined by the provision of value to the enterprise, as set out in the vision, mission, goals and objectives of that enterprise.

Although many different approaches to EA exist, a common thread running through them is the need for formal conection between the so-called architectural layers, represented by:

• Business Architecture, defining the processes, operation, context and motivation of the business;
• Information/Data Architecture, prescribing and defining the types of information relevant to the business;
• Systems Architecture, describing the logical behaviour of systems/applications in the context of the business;
• Technical Architecture, describing the physical infrastructure required to provide and support these systems.