The second section describes the method used to create a mental model:
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
The third section of the book describes how to apply a mental model to your work:
Chapter 12: Alignment and Gap Analysis
Chapter 13: Structure Derivation
The appendices and bibliography are available as links on the book site at
We recommend that you display the digital version of the book using a recent version of Adobe’s Reader or Acrobat Professional, which support live links. That way you can jump to other parts of the book (i.e., from the table of contents to a specific section) and to external web pages (such as the large, high-resolution version of each of the book’s illustrations, which we’ve made available via Flickr) by simply clicking. You’ll also find navigation easier if you display the Navigation Pane (in Apple’s Preview reader, the Drawer).
We’ve optimized the digital version of this book for being read and used on a computer. As digital books are still quite a new phenomenon, we’d love your suggestions for how to do improve our digital design; please contact us at [email protected].
What comes with the Book?
This book’s companion web site (
A variety of Excel and Word templates (including ones that help you with recruiting and capturing behaviors)
Scripts for converting Excel and Word templates into XML Visio and Omnigraffle diagrams
Every diagram in the book (download and insert them in your own presentations!)
The book’s bibliography
Appendix A: How Much Time and Money? (learn what’ll it cost you to develop mental models)
Appendix B: The Evolution of the Mental Model Technique (learn how this method came to be)
The book site also includes a blog where an occasionally lively discussion of mental models breaks out; please join in!
You can keep up with book-related announcements, new content additions, and other changes on the site by subscribing to its RSS feed:
Here’s How You Can Use Mental Models
You might make a mental model for a lot of reasons. For example, you can improve project management by studying those who coordinate project teams. Or, you can invent a new commuting service by understanding all the aspects of how people get to their jobs. You can capitalize on the gaps between the solutions you offer and what your customers are trying to accomplish. You can derive the architecture of your design from the resulting diagram. While the words I am about to list may sound dated when you read this book in a few years, I’ll go ahead and say them (so you can envision it more easily in the present day). This method can be used for:
Digital products, such as internet applications
Physical products with interactive functions, such as a watch
Location-aware products, such as a phone
Methodologies, such as project management
Information delivery, such as a monthly statement
Services, such as controlling your household’s carbon footprint
Physical spaces for providing services, such as a library
Browsable databases, such as knowledge bases
Platform-specific networked applications
Online media, online stores, etc.
You get the idea. Throughout this book I use the word “design” to mean something closer to “engineering design”—making something for someone to use. There are tons of other definitions for “design,” but for this book I focus on just this one aspect. So when you read the word “design,” think of digital, physical, and environmental interactions that people carry out to accomplish something.
Mental model diagrams have been used for design by for-profit and non-profit organizations, universities, government agencies, private individuals, and internal departments. I will illustrate the breadth of applications throughout this book with analogies and real-life examples.
One thing to take from this book is a sense of moving beyond constraints. You’re probably not a strict rule-follower, yourself. Just because my background is software design doesn’t mean you can’t use mental models to develop a government building or a production workflow or anything else you need. Merge the technique with its established cousins in your particular field of expertise, and tell the rest of us how you did it. Treat it kind of like open source: It is yours to manipulate and extend. Let everyone else benefit from your contributions.
My hope is that our generation of designers can execute an inflection point that will be remembered as the point in time when we stopped designing by necessity.
Frequently asked Questions
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 What is a Mental Model? for more information.
What if I don’t have a big budget?
If your organization already conducts usability tests 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 test and half on conducting a non-leading interview.
What do you mean