The 4D Process is founded on and incorporates the ISD model in all of its consulting and development production. By definition Instructional Design is the practice of arranging media and content to help learners and teachers transfer knowledge most effectively. The process consists broadly of determining the current state of learner understanding, defining the end goal of instruction, and creating some media-based "intervention" to assist in the transition. The outcome of this instruction may be directly observable and scientifically measured or completely hidden and assumed.