This paper describes how to develop a hybrid formulation for calculating the scatter signature of various shaped targets. Computational electromagnetics (CEM) is a vital tool used to treat many problems arising in a wide variety of system applications. These system application areas include communications, radar, biological modeling, high speed circuitry, surveillance system analysis and design, antenna array technology, antenna platform interaction, fusing studies against low observable vehicles, and low observable vehicle (land, air, and sea) development. These are some of the major areas of importance in the developmental technology of today. Powerful tools and algorithms result from this work that can make the computation of very tedious and complex research and engineering problems/projects involving such technology as electromagnetics challenging and exciting. The hybridization of the fast multiple method (FMM) and the physical optics method (POM) is described, and the results for the hybridization of FMM-POM and the individual FMM and POM implemented on a parallel computer are presented and compared. The FMM-POM hybridization is an optimization for best accuracy and minimum computational operations(time). Individually, the FMM is most accurate and the POM is least accurate; this is true most of the time, except for simple geometrical surfaces when the accuracy is approximately equal.