Mental Models Cover

Mental Models

Aligning Design Strategy with Human Behavior

By Indi Young

Published: February 2008
Paperback: 299 pages
ISBN: 978-193382000604
Digital ISBN: 978-1933820-19-4

There is no single methodology for creating the perfect product—but you can increase your odds. One of the best ways is to understand users’ reasons for doing things.  Mental Models gives you the tools to help you grasp, and design for, those reasons.  Adaptive Path co-founder Indi Young has written a roll-up-your-sleeves book for designers, managers, and anyone else interested in making design strategic, and successful.

Hear author Indi Young on The Rosenfeld Review Podcast

Paperback + Ebooks i All of our Paperbacks come with a FREE ebook in 4 common formats.


Ebooks only i All ebooks come in DRM-free Kindle (MOBI), PDF, ePub, and DAISY formats.


More about Mental Models


Indi Young’s new book is a welcome addition, covering an aspect of the design process that is extremely important but often neglected. The book is chock-full of practical advice derived from real-world development projects, but doesn’t lose sight of the broad conceptual underpinnings.

–Ray Valdes, Research Director, Web Services, Gartner Inc.

Mental Models offers a practical set of techniques for task analysis in the early stage of design thinking and strategic design planning. Developed over the course of more than ten years, Indi Young’s common sense approach focuses on user behavior, diagrammatic representations, and the participation of all stakeholders in collaborative discovery. It is a book that designers and students, alike, will find useful.

–Richard Buchanan, Professor of Design, School of Design, Carnegie Mellon University

At Dow Corning, Mental Models offer understanding at many levels—from a high level overview of customers’ generic unmet needs, to providing a detailed examination of the atomic tasks that they carry out as part of their jobs. So too for this indispensable book—it offers both a high level overview of the value of Mental Models for executives and leaders, as well as a detailed step-by-step guide to the technique for practitioners. Indi has eloquently captured the essence of Mental Models and offers her unrivaled experience to everyone.

–Simon Parker, Global Process Manager, Front End of Innovation, Dow Corning Corporation

Mental models reveal all those things that should be obvious during the design process, but so often come back to haunt you later. Indi’s book provides a systematic and invaluable means for applying mental models; having used her method on many large projects, I’m a true believer.

–Camille Sobalvarro, Senior Director, Web Marketing & Communications, Sybase Inc.

Table of Contents

  • Chapter 1: What and Why? The Advantages of a Mental Model
  • Chapter 2: When? Using Mental Models with Your Other Work
  • Chapter 3: Who? Mental Model Team Participants
  • Chapter 4: Define Task-Based Audience Segments
  • Chapter 5: Specify Recruiting Details
  • Chapter 6: Set Scope for the Interviews
  • Chapter 7: Interview Participants
  • Chapter 8: Analyze the Transcripts
  • Chapter 9: Look for Patterns
  • Chapter 10: Create the Mental Model
  • Chapter 11: Adjust the Audience Segments
  • Chapter 12: Alignment and Gap Analysis
  • Chapter 13: Structure Derivation


These common questions about web accessibility and their short answers are taken from Indi Young’s book Mental Models: Aligning Design Strategy with Human Behavior. You can find longer answers to each in your copy of the book, either printed or digital version.

  1. What is a mental model?
    The top part of the model is a visual depiction of the behavior of a particular audience, faithfully representing root motivations. The bottom part of the model shows various ways of supporting matching behaviors. Where support and behavior are aligned, you have a solution. Where a behavior is not supported, you have an opportunity to explore further.
    See page 2 for more information.
  2. What if I don’t have a big budget?
    If your organization already conducts usabilitytests with some regularity, piggyback short interviews on top of each session. Ask the participant to stay with you for an hour, and spend half the time on the usability testand half on conducting a non-leading interview.
    See page 57.
  3. What do you mean by “task?”
    The word “task” is used loosely. When I use the word “task,” it means actions, thoughts, feelings, and motivations—everything that comes up when a person accomplishes something, sets something in motion, or achieves a certain state.
    See page 207.
  4. What are task-based audience segments?
    Task-based audience segments are, quite simply, groups of people who do similar things. While personality types do touch upon behavior, generative research for building mental models requires that you select from groups of people who want to get different things done. Because you will want to tailor your end solutions to fit each audience exactly, grouping audiences by differences in behavior is important. You want to end up with solutions that match behaviors and philosophies closely rather than with one solution that fits several audiences loosely. Figure out what people want to accomplish, look for differences, and group accordingly.
    See page 74.
  5. How do I uncover the root task?
    During analysis, you are required to interpret a little. This is the “art” to the process. You will find it easier if you ask yourself, “What is this person really trying to do?” The idea is to simplify to the “root” task.
    See pages 211 and 218.
  6. What do you mean by a content map’s “content”?
    Let me assure you that the name “content” does not limit your map to text documents.Your content map should include all the ways you serve people, including things like monthly account statements or yearly awards banquets, registration for training courses, or a mortgage calculator.
    See page 354.
  7. Does a content map show every detail of my solution?
    It includes all functionality that exists or is intended for your solution.
    See page 354.
  8. How can analyzing gaps in a mental model show me innovative ideas?
    The first thing to look at is the obvious gaps where there is an absence of content items. Your hope is that you can find a gap that you can fill easily. Then look for scarcity of content items. Think about where you can flesh out things a bit. Look for opportunities to redefine, combine, or augment existing content.
    See page 377.
  9. How can mental models help me make sense of all my web properties?
    Each one of your web properties is a building on your internet campus. Each property has its own unique navigation that represents the mental model of the people populating it.
    See page 324.


  • Chapter 7 (PDF)

Book Reviews

Journal & Association Reviews

Reviews from Various Blogs, Companies, Consultancies, Organizations

Case Studies

Mental Model Sketches by Indi

Real Examples by Real Organizations

These example diagrams are the work undertaken by companies around the world. I am grateful for their permission to post each example. In some of the examples, the slotted content has been “grayed out” with respect to the privacy of the company donating the diagram. The upper half of the diagrams were each deemed “pretty much public domain knowledge.” Or else the photos were just taken at a distance where the proprietary data can’t be read.

If you would like to donate your organization’s diagram, please contact me.

Student Examples

Photos of Mental Models Around the World


*Note: Many links below are currently broken. We’re working on it, but in the meantime, you can find most of the resources in this zip file.

Background for Your Boss (or Client)





    • Slide decks: some full audio and some summary decks from several presentations I’ve given.
    • Video: Presenting Sparking Creativity Through Empathy (42 min) at the IIT Design Research Conference, Chicago, IL – September 2008
    • Video: Presenting a Google TechTalk Digging Beyond User Preferences (1 hour 3 min) at Google, Mountain View, CA – July 2008
    • Video: Presenting a Yahoo TechTalk Empathy & Innovation (1 hour 10 min) at Yahoo, Sunnyvale CA – April 2008 – [post]




  • Online seminar: Getting Into Your Customer’s Head (2 hours, for a fee) in association with UIE – Feb 2008
  • Book Club Meeting: Live tweet summary of helpful tips I mentioned at the UX Book Club meeting about mental model diagrams, Philadelphia, PA – May 2011



Short-Cut The Process

Employ the Model Over the Long Term

Segment Audiences by Behavior for Recruiting

Recruit Participants

Find Out What Makes People Tick: Gather Stories

Comb Through the Transcripts

Format the Model

  • To make the diagram look professional, Use Proper Case in all the titles and boxes.
  • The height of the towers does not signify anything, really
  • More on printing mental model diagrams, with real-life examples.

Slot Content Beneath the Towers

Derive Information Architecture & Design

Run the Project

Templates & Scripts



“You’re researching all the creativity out of this project!”

I can’t tell you how many times I’ve heard designers, developers, and even business owners say this. It usually comes just after a project has begun, as I’m preparing for interviews with users. Designers just want to start designing, developers want to start writing code, managers want the thing to ship—so why are we spending all this time talking? And all this stuff just seems so obvious. Do we really need users to tell us what we already know?

I try to be diplomatic. “Maybe a few interviews now will save us lots of grief later,” I tell them. “Think of this as insurance: Let’s make sure we’ve got the basics right before we’ve designed everything and written all the code.” But no matter what I say to convince a team to do research early in their project, I never let them know my dirty little secret: I used to be just as skeptical as them.

I’ve always believed in a user-centered design methodology. Even early in my career, when I was a journalist, we always started with the mantra “know your audience.” Later in my career, I’d go to conferences and watch presentations with process diagrams—boxes representing users needs with arrows pointing to boxes representing product requirements.

Intellectually, I agreed. But when I started a new project, in that intoxicating first stage when anything is possible, I’d jump straight to solutions. “Let’s use Flash for this part! And over here, we’ll design some awesome icons for navigation…” Our users were still important, but they were there to bear witness to how cool our designs were.

Then I met Indi Young. Indi and I were among the founding partners of Adaptive Path, a user experience consulting company that focused on research-driven design. Wefounded the company in the dark days of the Web industry. It was 2001. “Dot com” was a dirty word, companies were cutting their Web budgets, and projects were drying up everywhere.

It was then that “research-driven” started having real meaning to me. As Indi introduced her methodology and resulting visualizations, it became clear that she wasn’t just trying to make designs better in some abstract way. Rather, her process was simple enough to resonate with anyone on a Web team. And perhaps more importantly, it would help connect Web teams to other core parts of their organizations who were skeptical of spending even another cent on their web sites.

In the end, using Indi’s process, we were able to convince teams that we weren’t researching all the creativity out of their projects. We were researching the risk out. And no matter how the industry is faring, that’s a story people want to hear.

This book is an excellent guide to a research method firmly grounded in common sense. But don’t let the simplicity of the process detract from the power of the change it can enable. Talking to users in a structured way, analyzing in a collaborative way, and diagramming with clarity can transform the way you approach the Web.

And it might just ignite your creativity!

Jeffrey Veen
San Francisco, August, 2007


I would like to thank the following people for their influence on the mental model method as it continues to mature over time:

Mary Piontkowski, who is not afraid to point out where I might be wrong-headed. Thank you.

Gina Davis and Paul Stiff, who saw the strengths of early mental models and encouraged me to develop the method.

Jim Hook, who told me that what I thought was common knowledge might not really be as common as I supposed.

For beta-testing draft chapters and clearing up confusion: Craig Duncan, Simonetta Consorti, Andrea Villa, Jen Richardson, Isabelle Peyrichoux, Ingrid Hart, Marcus Haid, Ginny Redish, Todd Wilkens, Brandon Schauer, Ryan Freitas, Bjorn Hinrichs, Jay Morgan, Jon Littel, Lauren Kessler.

Clients who believed in the possibilities: Camille Sobalvarro, Yen Lee, Suneet Wadhwa, Karen Wallace, Joelle Kaufman, Lee Thompson, Terie Clement, Joel Arabia, Karen Semyan, Carey Wilkins, Renae Gottschall, Paola Dovera, Mark McCormick, Secil Watson, Georgina Corzine, Connie Frennette and Clare Barr and Kathy Parsons (the “Kh” team), Srinivas Raghavan, Hanneke Krekels, Simon Parker, Jim Mier, Tim Adams, Jackie De Muro, Bob Bebb, Lakshmi Sundar, Dan Arganbright, Suzanne Van Cleve, Bryan Vais, Eric Fain, Tom Gruber, Peter Ostrow, Maclen Marvit, Enrique Alvarez, Matthew Nelson, Chad Carson, Christina Avrett, and Kevin George, who was the first person to say, “You should write a book about this,” while we were riding in a taxi out of Pasadena, in September 2000. Real examples make all the difference when explaining something. I want to thank all my clients who gave me permission to publish our work.

Teammates Donelle Gregory, Evelyn Wang, Mark Phillips, Carolyn Snyder, Laurie Bell, Chris Baum, Jen Klafin, Nate Bolt, Genelle Cate, Jean Anne Fitzpatrick, Darcy DiNucci, Adele Framer, Dave Covey, Chiara Fox, Sarah Rice, Kate Rutter, Lane Becker, Mike Kuniavsky, Peter Merholz, Jesse James Garrett, Janice Fraser, and Jeff Veen. And Gary Wang, who wrote the first Python scripts that spit out the diagrams.

I could not have done this without all the good people involved in production at Rosenfeld Media: Karen Whitehouse for inflating my ego. It’s her fault that I’d like to write another book. Peter Morville for sending me an email out of the blue offering to do a technical review; I can just imagine him sitting down at his desk that morning thinking, “Gee, I have nothing pressing to do. I think I’ll offer to read Indi’s manuscript.” Right? Liz Danzico and Allison Cecil for taking everything off my hands and making my part in the production process blissfully easy. Marc Rettig, whose comments on the “mental models versus alignment diagrams” debate, as well as the book’s positioning, were quite helpful early on. Lou Rosenfeld for having the determination to start Rosenfeld Media and do something right. It is pure joy to work with him and watch his publishing philosophy unfold. I am confident that his efforts will force a sea-change on the industry.

I owe my sanity during the writing of this book to my friends: my mom, Gus Young, graduated high school in 1958, and won a four-year scholarship to a university to study math. If she hadn’t turned it down in order to help support her seven siblings, I am convinced she would have been one of the first software engineers. Yes, her name is Gus. My brother, Greg Young, for urging me to write a book, any book. Philip Ramsey for urging me to continue writing after dinner while he did the dishes. Carolyn Wan for making me laugh with email about her three young daughters. I wish I could tell stories like she does. Lucy Simon for moral support and distracting workouts at the pool. Matt Stephens for all the phone calls when I was frustrated with words. Marjorie Forman for keeping me from being too much of a recluse. Carey Ritola for celebrating my 15 minutes of fame.

And for her constant presence curled up napping on my desk: Megahertz (13 January, 1988-21 June, 2007), my 19 year old cat who was really a space alien, I’m sure.