1. A method for assuring that the operator of a vehicle is an authorized driver, the method comprising: utilizing an onboard, multi-mode driver verification system to ascertain whether an operator is an authorized driver; performing a first driver verification procedure on a present operator of the vehicle and determining whether the present operator is an authorized or unauthorized driver of the vehicle; performing a second driver verification procedure on the present operator of the vehicle and determining whether the present operator is an authorized or unauthorized driver of the vehicle, wherein the first and second driver verification procedures are performed with a time interval therebetween, the time interval being dependent upon the nature of the work being performed by the operator and upon one or more of a frequency of vehicle stops and a frequency of times the operator enters into and exits from the vehicle; exercising a remedial measure to avert potentially negative impact when the present operator of the vehicle is determined to be an unauthorized driver based upon at least one of the performed verification procedures; and wherein at least one of the verification procedures comprises utilizing biometric data that can change over time for a particular person thereby potentially permitting an verification failure of that person based on a comparison of current biometric measures against a previously-produced template of the same characteristics, and automatically updating the previously-produced template.