A call center for handling requests for medical transportation utilizes a system that assists a call center agent by automatically determining, or prompting the agent to ask for, all information needed to assess the level of service required and the effects of any applicable contractual provisions. The system captures information relating to the patient and the requested transportation, and applies service level rules representing the applicable regulatory requirements for medical transportation at the location of the patient to determine the required level of service based on the patient's condition and needs. The system further applies business rules representing the contractual provisions that are applicable to the requested transportation to determine responsibility for the cost of transportation, the authority of the requester to change the level of service or other aspects of the transportation, and the responsibility for the cost of transportation in the event that an aspect of the transportation has been changed.