The 3DID system has been developed to verify the identity of a person by matching a sensed 3D surface of the face to a face model stored during an enrollment process. Anchor point detection is performed based on shape index; then, a rigid alignment is determined between the observed and model face anchor points. The alignment is refined using a modified ICP algorithm allowing for trimming of 10% noise. Trimmed RMS error for the same person is almost always smaller than 1.3mm; whereas for different persons, it is almost always larger. Performance analysis shows that the 3DID system is fast enough (\ge 2 sec on a 3.2 MHz P4), reliable enough (1% EER with 1.5% reject rate), and user friendly enough (handles 30 degrees of yaw and 10 degrees of roll and pitch) to be practical in several applications. The current system provides several displays of value to human agents either in online or delayed analysis mode. An inexpensive scanner is needed for widespread use.