I once attended a design talk, where Bill Buxton was also in the audience. During the Q & A part of the session, Buxton made few comments about the important role of transitions in interaction design. I found his comments insightful, and I wanted to learn more about his thinking behind them. He also mentioned a book he was writing, and that was the first time I heard about it. I e-mailed him for more information about the book, and I later bought a copy when it was available. Since then, I've met with Bill Buxton a couple of times and have learned a few more things from him.

If you're a software or interaction designer, this book definitely belongs on your bookshelf. I found his book to be a good complement to Schrage's; although, Buxton makes a clear distinction between a 'sketch' and a 'prototype'. Regardless, his book changed my approach to designing within the software development process, and how I work with my engineering team. The results have been very positive.

And don't be misled by the word 'sketching.' You don't need to be an artist. To start, all you need is a pencil and paper.