Instructional Design

Iterative Design Models: ADDIE vs SAM

Want to add some dazzle to your ho-hum corporate learning or training session?

Creating engaging eLearning experiences has obvious benefits for your learners: adding dazzle requires time and attention to design. 

While there are many paths to perfect instructional design, iterative design models can help you get organized before testing and executing your plan. The two most well-known iterative design models, ADDIE and SAM, represent very different methods for designing eLearning.  

Choosing  whether ADDIE or SAM is best suited for employees and learning goals presents an interesting debate for designers.  Let’s take a look at the differences, strengths, and weaknesses of each to help you settle the age-old ADDIE vs SAM debate. 

But First: a Definition

Merriam-Webster defines iteration as “a procedure in which repetition of a sequence of operations yields results successively closer to the desired result.”

It might seem like a stodgy approach to a creative solution, but without an iterative design process, it’s likely you’d end up with eLearning solutions that look great, but miss the mark on content. . 

The ADDIE Model

The ADDIE model (Analysis, Design, Development, Implementation, and Evaluation) incorporates a succession of iterative steps. The team carefully considers, debates, and implements each step before moving onto the next one.

It’s not uncommon for each step to undergo several iterations before the team is satisfied.  Imagine writing and editing the first draft of a book, one chapter at a time. You perfect one chapter at a time before beginning the next. It takes time and can be emotionally (and professionally) draining, but it’s all in pursuit of the perfect result. 

The phases of ADDIE are cumulative, meaning that each step builds on the previous step. It’s methodical and ideal for Type-A list-lovers. 

Unfortunately for the perfectionists of the eLearning design world, project goals change and can throw the entire process all the way back to the analysis phase, slowing the development and busting the implementation calendar.

SAM (Successive Approximation Model)

ADDIE is often described as “ready, aim, aim, aim, fire”; SAM (Successive Approximation Model), is more like “ready, fire, aim.”

If you think well on your feet and love the rush of meeting a deadline dead-on, SAM might be a better fit for your process.

SAM is a rapid development model that uses a continuous iterative design process throughout the lifecycle of development rather than taking it one linear step at a time. 

SAM starts with a rapid prototype, with analysis and design happening at the same time at a fast and furious pace.  The first iteration of a SAM-developed eLearning might require an overhaul because unlike ADDIE, SAM doesn’t require buy-in at each stage. Instead, SAM relies on quick solutions, testing, and pivoting along the way. When you’re under the gun and have to get something out yesterday, SAM makes perfect sense. 

Still, there are risks that once the process is complete, missed steps or unrealized challenges could send you back to the drawing board for a total revamp. The key to surviving SAM is understanding that nothing is carved in stone and no one is married to their ideas. 


The battle between ADDIE vs. SAM rages on between perfectionists who love the ADDIE model, and SAMsters who prefer to fly by the seat of their pants and like the challenge of SAM.

Tight deadlines or a lengthy design process? One set in stone solution or lots of options? The project scope ultimately guides the iterative design model that works best for you.