Designing the human-facing behavior of software-powered systems is a relatively new discipline. As any new discipline develops, even its own practitioners are unaware of its ultimate scope, and the breadth of expertise its application requires often comes as a surprise even to its most skilled experts. It certainly surprised me to see just how deep the craft really went as we explored it. The depth of knowledge and the extent of method required is significant, and it truly represents a unique discipline of some magnitude.

This book is the first I've ever read that covers the entire spectrum of interaction design practice as a craft, including visual design and industrial design. While interaction design is a wholly new discipline, visual and industrial design are older, pre-existing fields that have been wholly transformed by digital technology. All three are given full consideration here. Others have written scholarly work on the theoretical underpinnings of software behavior, or described the visually aesthetic component of the field. Some others have attempted to cover the entire ground, but at one point or another, all of them take leaps of faith, exhorting the budding practitioner to "be creative" or "make it easy to use."

But practitioners need to know how to make it easy to use, and how to be creative. Gaining mastery of these tiny, creative steps is precisely the sticking point that leaves the student of interaction design unable to proceed. Kim's comprehensive book never advocates such leaps without giving the reader detailed instructions on exactly how one goes about making them, and with real world examples. The primary reason why this book will change the way designers learn and practice their craft is because of the thoroughness with which it covers the great span of the field.

Unlike so many of the new disciplines ushered into being by the digital revolution, the design of digital artifacts isn't purely technical. While it is abundantly rationalist and demanding of rigor, it contains generous helpings of cognitive psychology, sociology, and ethnography. One of the reasons why it is a craft distinct from programming is simply because most programmers, who otherwise so value cross-discipline skills, are quite disinclined to include the skills of observation, interviewing, and analysis of the humans who will ultimately use their creations. Interaction designers need to learn the techniques and patterns that empower them to understand humans, as well as software.

The wisdom and methodology set forth in this book is the product of many minds working at my company, Cooper, while operating on many client engagements, over a span of 17 years. Here at Cooper we follow a Socratic method, where, although clever answers are valued, discriminating questions are valued more. The dialogue is what brings forth not just solutions, but also entire frames of reference for how to approach problems in any domain and deconstruct them for solution. And we keep on learning, constantly changing and growing the method and its toolset.

At times, each of us here has played the role of teacher, and each the role of student, and our attention is always on finding the underlying principles. The axiomatic nature of such fundamentals allows the practitioner to build his or her skill over time by seeing the common forces and patterns at work both in the man-machine interface and in the process used to create solutions for that interface. All great craft disciplines share this trait; while their essence can be expressed in a few simple aphorisms, the mastery required to put those aphorisms into practice can take years to learn and decades to master.

Kim Goodwin has been a prime participant in the dialogue at Cooper since 1997. She has been one of the major contributors to the development of our design methodology. She is an authority on design, problem scoping, engagement management, and design documentation. Kim has labored in the trenches in a broad variety of design segments, from clinical medicine to conceptual blockbusting. She has led groups of designers, coordinating their work, and synchronizing it with the needs of some very demanding clients.

And she has taught others to design. Many hundreds of people have gotten a taste of Kim's clarity, patience, thoroughness, and rigor by attending her presentations at conferences, her one-day field seminars, or her design courses. In fact, Kim has been the primary creator of training content for our very successful Cooper U classes. Over the years, her particular expertise at observation, synthesis, and communication while in charge of other design teams and honed in the classroom, led her naturally to write this book. Much of the content and wisdom gleaned from those classes is evident here.

Cooper's Goal-Directed Design is a unique and effective method. It is a collection of practices and principles that are used the way any craftsman uses his toolset. On any given project there are tools that are always used. Some tools are used regularly but not always, and some tools are used rarely, but when they are needed they are the only way to get it right. A big part of the skill of the designer is in knowing what tools are available and having the experience to know which one to apply for best effect. Kim provides the strategies for selecting and applying them in professional use.

The firm foundation of the method doesn't take away from your creativity as a designer. There are lots of easy design problems in the world, but there are also lots of very difficult ones. Glib cleverness may work for the former but will leave you afloat in a sea of confusing variables in the latter. The great value of a rigorous methodology is that it gives you a strategy for breaking down the really complex, tough problems into smaller, more familiar, and more manageable tasks that can be readily addressed. While personal creativity helps you create the right answer, mastery of the overarching process helps you address the right problem.

Clients regularly bring to us some of the hairiest, most complex problems set in the most politically demanding situations imaginable. While some agencies shy away from such apparent no-win propositions, we revel in them because of our confidence in our tools. When a software giant, for example, wants us to design a financial application for millions of users, or when a medical services company wants us to design a clinical application for orthopedic surgeons to use during hip replacement operations, our designers put on their green eyeshades or hospital scrubs, and wade in with manic glee, knowing that observation, methodology, experience, and a comprehensive set of effective design principles will reveal the hidden forces at work and allow them to synthesize world-class design. The book you are now holding gives those tools—and that confidence—to you.

If you are just starting out in the world of designing digital products and services, this book will take you step by step through the process of interaction design, from initial ethnographic research, through ideation and design, all the way to final delivery and presentation. Even if you are an experienced designer, this book will help bring a new level of professionalism and efficiency to your practice.

This book is comprehensive in its scope, exhaustive in its depth, authoritative in its practice, and priceless in its wisdom. It will certainly become the anchor document for an entire practice. While I expect to see it on the bookshelves of every practicing designer, I further expect that it will spend the lion's share of its time off the shelf and at the elbow of hard-working designers. I've no doubt that this will become the most dog-eared, annotated, and worn-from-many-readings volume in your library. Most certainly, it will also reshape university curricula and inform the next generation of practitioners.

While my own books have served as either introductory or motivational, Kim's book is nothing less than a complete handbook for an entire profession. Kim's unique background in the practice, pedagogy, and epistemology of the design business has given her the experience needed to write the ultimate "how-to" book of technology design. Every step in this fascinating and multifaceted discipline is described in detail in simple, readable prose, richly illustrated with examples taken from real products, real clients, and real design problems. I know you will come to regard this book as indispensible.

Alan Cooper

Founder and Chairman, Cooper

San Francisco, California