The DES Program was developed using the framework of instructional design guidelines within a systems approach model.

A system is technically a set of interrelated parts, all of which are working together toward a defined goal. The parts of the system depend on each other for input and output, and the entire system uses feedback to determine if its desired goal has been reached. If it has not, then the system is modified until it does reach the goal. The purpose of the system is to bring about learning. The components of the system are the learners, the instructor, the instructional materials, and the learning environment. These components interact in order to achieve the goal. The systems approach models are an outgrowth of more than twenty years of research into the learning process.