From Dr. Stanley C. Plog's article, "Travel's Past and Future: A Big Picture Will Get Even Bigger"

To fathom the future, you need to know the past. The wealth of vital data supplied in the Travel Industry World Yearbook - The Big Picture provides a basis for doing that. But sometimes it's difficult to find the forest (dominant trends) because of the trees (lots of data). Thus, it can be useful to present a broad overview of what has happened recently, and some of the emerging trends that will impact just about everyone associated with this ever-changing, dynamic industry.
     By now, just about everyone knows that travel is the largest industry in the world, according to the World Tourism Organization. That's quite an accomplishment. It exceeds huge industries like automotive, agriculture, health care and technology. When I completed my first big travel project, about 35 years ago, it ranked about 12th in the US and the world, and puny in comparison to the giant industrial categories. So, it has achieved remarkable growth for a variety of reasons. But it also faces short-term problems caused by the 9/11 terrorism attacks on the World Trade Center in New York City and the Pentagon in Washington, DC, along with the softening of economies in almost all regions of the world over the past three years. Airlines have gone bankrupt, hotel occupancy and rack rates have dropped significantly, and destinations struggle to find new ways to attract visitors to offset often dramatic declines in tourists and tourism revenue. And it also faces difficulties that are self inflicted and will become more apparent in the future.

This is the one reference book that pulls all the disparate parts of the multifaceted travel industry together and provides an overview of the industry on a worldwide basis. The Travel Industry World Yearbook is subscribed to by key members of the travel industry in more than 100 countries around the world.

This cache of information analyzed and updated annually includes: advertising and promotional expenditures detailed by industry segment, state, and country. It has facts about destinations, transportation, accommodations, food service, car rentals, cruise lines, travel agencies and tour operators.

It contains the detail necessary to determine how tourism impacts economies by number of jobs, balance of international payments, and many other critical factors attributable to the industry.

In addition, its index will help you navigate the information trail in 250 plus cities, states, and countries.