Perhaps the greatest fundamental deterrent to the application of current laser ultrasonic technology has been the fact that the detection sensitivity or detectability of laser receiver systems, compared with their piezoelectric counterparts, is rather poor. That is to say that in general, and especially on a dollar-for-dollar basis, piezoelectric transducers are able to detect much smaller surface displacements than can easily be detected by laser methods. As will be discussed shortly, there are several strategies which may be used to overcome these detectability shortcomings. Indeed, several of these strategies have been investigated at the laboratory level and some implemented in full-scale systems which have been demonstrated to perform reliably and with good detectability even in an industrial or field inspection application [1]. In this latter case, however, the successful strategy pursued to improve laser ultrasonic detectability limits has not been inexpensive in terms of the cost of laser equipment necessary to reach satisfactory performance levels. Nevertheless, there are several inspection and process control applications where critical structural and materials property information can only be obtained by remote noncontact ultrasonic inspection, thus justifying the expense of such a sensor system.