Abstract: Aspects of the disclosure provide for arranging a trip in an autonomous vehicle without a driver. For instance, a request may be received from a client computing device associated with a first person to arrange the trip for a second person. The request may include a pickup location for the second person and a destination location for the second person. An authentication method may be identified for the trip. A signal may be sent to the autonomous vehicle in order to cause the autonomous vehicle to maneuver to the pickup location, authenticate the second person using the authentication method, and transport the second person to the destination location.