A book of this scope is not produced by a single person within a short time period. As the author responsible, I wish to utilize briefly the first-person singular form to acknowledge my indebtedness to organizations and individuals. Teaching transportation planning courses at Columbia University for many decades has given me an opportunity (nay a necessity) to keep abreast of the field, and I thank my students for their questions and concerns, which have shaped and steered my own attitudes more than they know. Being active in a field for a long time does not necessarily bring wisdom, but it does generate experience and a sense of reality and opportunity as situations keep changing. My academic involvement has been complemented, rather extensively, I think, by work on numerous transportation projects in some 25 countries. I have done this primarily as the technical director for planning and vice president of Parsons Brinckerhoff, a consulting firm with an international standing in the field of transportation, but also in association with other organizations, such as various municipal governments and the United Nations. I remain an unabashed New Yorker, my permanent home by choice, even though I have the opportunity now to be active also in my native country, Latvia.

My consulting and academic work has had the added informative but tiring dimension of extensive travel. I have seen and at least touched

For rapid transit, I define this as riding every line from beginning to end, past every station.

just about all the...