This paper describes a three-dimensional ray tracing model for predicting ultrasonic energy propagation in anisotropic and inhomogeneous materials. The model has recently been developed to be an iterative tool, capable of calculating energy paths between specified start and end points. This two-point ray tracing is presented and its value for predicting energy paths between transducers and postulated defects is discussed. Applications of the model to problems of interest to ultrasonic nondestructive testing are presented. These include assessment of inspection methods for austenitic components, such as cladding and welds. In particular, defect location and sizing errors are calculated for underclad defects at a variety of depths below a layer of cladding, and for backwall breaking defects in and around a single V-weld. For the calculations considered, we find these errors generally to be small, except for defects close to the cladding layer, where significant underestimation of the distance between the top of the defect and the cladding occurs.