Crossing the Chasm deserves more than five stars for putting "a vocabulary to a market development problem that has given untold grief to any number of high-tech enterprises." Crossing the Chasm is the most influential book about high technology in the last 10 years. When I meet with CEOs of the most successful high technology firms, this is the book that they always bring up. What most people do not realize is that Geoffrey Moore did an excellent update of the book in a revised edition in 1999. If you liked the original, you will like the revision even more. It contains many better and more up-top-date examples, and explores several new ways that companies have crossed the chasm that he had not yet observed in 1991 when the original came out (such as "piggybacking," the way that Lotus 1-2-3 built from VisiCalc's initial success). If you plan to work or invest in any high technology companies, you owe it to yourself to read and understand this book. The understanding won't be hard, because the material is clear and well articulated. The book's focus is on a well-known psychological trait (referred to as Social Proof in Influence by Robert Cialdini). There is a potential delay in people using new things "based on a tendency of pragmatic people to adopt new technology when they see other people like them doing the same." As a result, companies must concentrate on cracking the right initial markets in a segmented way to get lots of references and a bandwagon effect going. One market segment will often influence the next one. Crossing the Chasm is all about how to select and attack the right segments. Many companies fail because innovators and early adopters are very interested in new technology and opportunities to create setrategic breakthroughs based on technology. As a result, these customers are not very demanding how easy it is to use the new technology. To cross the chasm, these companies must primarily appeal to the "Early Majority" of pragmatists who want the whole solution to work without having to be assembled by them and to enhance their productivity right away. If you wait too long to commercialize the product or service in this way, you will see your sales shrivel after a fast start with the innovators and early adopters. The next group you must appeal to are the Late Majority, who want to wait until you are the new standard and these people are very price sensitive. Many U.S. high technology companies also fail to make the transitions needed to satisfy this large part of the market (usually one-third of demand). The final group is technology adverse, and simply hopes you will go away (the Laggards). The book describes its principles in terms of D-Day. While that metaphor is apt, I wonder how well people under 35 know D-Day. In the next revision, I suggest that Desert Storm or some more recent metaphor be exchanged for this one. The book's key weakness is that it tries to homogenize high technology markets too much. Rather than present this segmentation as immutable, it would have been a good idea to provide ways to test the form of the psychological attitudes that a given company will face. The sections on how to do scenario thinking about potential segments to serve first are the best parts of the book. Be sure you do these steps. That's where most of the book's value will come for you. Otherwise, all you will have added is a terminology for describing how you failed to cross the chasm. I also commend the brief sections on how finance, research, and development, and human resources executives need to change their behavior in order to help the enterprise be more successful in crossing the chasm. After you finish reading and employing the book, I suggest that you also think about what other psychological perceptions will limit interest in and use of your new developments. You have more chasms to cross than simply the psychological orientation towards technology. You also have to deal with the tradition, misconception, disbelief, ugly duckling, bureaucracy, and communications stalls. Keep looking until you have found and dealt with them all! May you move across the chasm so fast, that you don't even notice that it's there!