SAM is a derivation of several models, including ADDIE, and a product of extensive experimentation and revision. In this white paper, Michael Allen, CEO of Allen Interactions, e-learning pioneer, and creator of the Successive Approximation Model (SAM), begins the paper by quickly covering the ADDIE process, why it was created and its makeup. Next, he discusses what iterations are and mean in SAM, how prototyping works, and the powerful brainstorming meeting known as the Savvy Start. Allen covers why SAM was created, and outlines the basis of the iterative prototyping model including Evaluation, Design, and Development. He goes on to share nearly 15 pages of the SAM process providing a comprehensive, yet digestible explanation of its phases and components including the Brainstorming Phase, Iterative Design Phase, and Iterative Development Phase. He also covers four contrasting advantages of SAM in comparison to other instructional development models like ADDIE.