Characterization of NDE transducers is an important part of current and future programs in quantative flaw detection. In the work reported here, emphasis has been placed on beam pattern measurements or profiling and circuit modeling of the transducer using electrical network scattering parameters, or S-parameters. The latter topic is relatively new and was developed in the last six to eight months in order to handle the problems of existing commercial transducers whose internal details are unknown. A subset of this goal is to: {a) explore single crystal or very high quality ceramic materials as the piezoelectric element, (b) examine the single disk in water as a transducer or reference element, and (c) look into electrical loading as an alternative to mechanical loading.