The enterprise architecture presents a view of how software utilities and applications are related to one another under unifying rules and principles of development. By constructing an enterprise architecture, an organization will be able to manage the components of its systems within a solid conceptual framework. This largely prevents duplication of effort, focuses the organization on its core technical competencies, and ultimately makes software more maintainable. In the beginning of 2003, several prominent challenges faced software development at the GBT. The telescope was not easily configurable, and observing often presented a challenge, particularly to new users. High priority projects required new experimental developments on short time scales. Migration paths were required for applications which had proven difficult to maintain. In order to solve these challenges, an enterprise architecture was created, consisting of five layers: 1) the telescope control system, and the raw data produced during an observation, 2) Low-level Application Programming Interfaces (APIs) in C++, for managing interactions with the telescope control system and its data, 3) High-Level APIs in Python, which can be used by astronomers or software developers to create custom applications, 4) Application Components in Python, which can be either standalone applications or plug-in modules to applications, and 5) Application Management Systems in Python, which package application components for use by a particular user group (astronomers, engineers or operators) in terms of resource configurations. This presentation describes how these layers combine to make the GBT easier to use, while concurrently making the software easier to develop and maintain.