American business will spend more than $100 billion on travel and entertainment by 1990, according to an American Express survey of business travel management. By comparison, an estimated $85 billion was spent in 1986, which American Express says is one-third more than business paid in taxes. The travel expense figure was $2 billion in 1985. Nearly 2,500 companies were surveyed and 28 percent responded, says American Express. According to the survey, air travel accounted for the largest portion of the travel and entertainment expenses, 41 percent of every travel dollar. Lodging (22 percent) and meals (17 percent) were next highest, followed by entertainment (14 percent) and car (6 percent). In the future, competition for business customers will focus on quality of service, according to American Express Travel Management Services. ``The competition for business customers is going to be won on quality of service, not price, as travel vendors respond to a high level of consumer discontent and focus on service issues,'' said Tomasso Zanzotto, president of Travel Management Services, in a 1988 business travel forecast. Brian Froehlich, of American Express Travel Management Services, says, ``There's a definite interest in delivering high quality service to companies and their travelers. We understand that quality is directly related to our success.'' A recent booklet from the American Society of Travel Agents, a trade association, reminded customers to plan ahead and ask questions of their travel agents: What is included in the price? What restrictions apply on discounted fare travel? What about passports and foreign currency? Travelmasters, a Chicago-based agency, is among those who have created information services to help customers make decisions. The agency has a Travel Line for special and last minute details for leisure travel customers and Fare Update, a monthly newsletter for corporate travelers and a Travelmaster Market Pack, containing travel costs, tour information, maps and weather information. ``As our business has become more computerized,'' says agency executive Peggy Blitz, ``it's more important than ever that we give meaningful service to each other.'' In another report, Runzheimer International said business travel prices rose sharply during 1987, increasing by 16.5 percent over the previous year. Runzheimer is a consulting firm based in Rochester, Wis. ``The reason for the big increase is due mostly to rising costs in air travel,'' said Brad Burris, executive vice president. ``The airlines tightened restrictions for travelers in 1987, making discount fares less available than in the past. Therefore, business travelers had difficulty fitting their schedules around the available low fare flights. Air fares rose 30.5 percent during the year, according to Runzheimer.