One of the foundations of instructional design is Robert Gagné's concept of the events of instruction. All good instruction, according to Gagné, requires a set of external events designed to support the internal processing of learning. He has identified a set of nine events listed below in the order in which they are usually utilized:

We often assume that event #4. Presenting the stimulus material, is what instruction is all about. However, without events #1 -3, students will not be prepared to receive the new information, nor without events #5 -9 will they retain or apply the new learning. Therefore, the entire cycle of the events of instruction is critical to promote learning.

Also note that events #5, 7, and to a certain degree #8 all rely upon the intervention of a skilled teacher. All the other events can be structured and presented through various forms of media and technology, but #s 5,7,8 require the intervention of a human's critical judgment.