The Chariot Shuttle Service Inc. (CSSI) makes money by providing transportation to customers in exchange for money. A typical day involves a shuttle van driving around the city, mostly between the airport and various locations. For example, a van may start the day by picking up three passengers from a local hotel and dropping them off at the airport. Two of these passengers are a husband and wife traveling together and the wife pays for both of them. (the couple is considered to be one customer, only the information of the contact person will be recorded in CSSI’s database). The other person just happened to be staying at the same hotel and had also called CSSI for a ride to the airport. This one trip to the airport thus consists of two service engagements. At the airport, six more passengers get on. Three of them are co-workers who need to go to a local manufacturing plant and whose corporation has an account with CSSI. One passenger needs to go to Hotel A and the other two passengers need to go to Hotel B. Customers may either be individuals or corporations.
CSSI owns many vans, each of which holds up to six passengers with luggage. A service engagement usually involves just one van, but sometimes will include more than one van. For example, if a corporate customer is sponsoring a training seminar, it might call CSSI and request several vans for one engagement to transport a large group of employees to another location. Every service engagement is the result of a reservation – customers either call CSSI to arrange the transportation they need, or they make reservations in person at the airport transportation desk. Some reservations are made weeks in advance, whereas others (such as airport desk reservations) are made only minutes before the transportation occurs. One telephone call may result in multiple reservations and in multiple engagements – for example, a customer may call and request