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เนื้อหาย่อ : Another EM Book? Several textbooks are currently available for teaching ectromagnetics to students majoring in electrical engi- ering. So, why do we need another one? The answer simple: (1) the curriculum for a bachelor's degree in ctrical engineering is undergoing a radical change, haps more radical in both outlook and content than of the curricular changes we have witnessed over past several decades, and (2) available textbooks are ompatible with the philosophy of the new curriculum oposed for the 21st century (see, for example, the arti- by Director et al. in the Proceedings of the IEEE, ptember 1995). Changing Curriculum For a bachelor's degree in electrical engineering, the ficulum has undergone about one major change per decade. In the 1960s, courses concerning solid-state derices were introduced and those on vacuum-tube dectronics were slowly phased out. In the 1970s, rses on electric machinery nearly disappeared from curricula of most universities and were replaced computer-programming courses. More computer- and digital processing courses were added in the 80s, mainly by increasing the volume of required uses and reducing the number of technical and free lectives. Also, there has been a sustained effort to orporate new knowledge and assimilate the rapidly lving role of technology in the undergraduate cur- calum. More material was added to courses, greater fort was expected from students, and the number of elective credit hours rapidly approached zero. By the 1990s, the average student at a U.S. university ed closer to five years to complete what was origi- designed as a four-year program. This scenario was not limited to electrical engineer- ing; indeed, in almost any engineering discipline, the curriculum had become too demanding in terms of time to complete the B.S. degree and too inflexible to accom- modate changes. From these pressures was born a new philosophy embracing the following tenets: (1) the B.S. degree program should be scaled back to four years, (2) the required part of the B.S. degree program should focus on the teaching of fundamentals, but with greater exposure to engineering applications, and (3) the elec- tives portion of the program should be increased sub- stantially to allow the student to explore both engineer- ing and nonengineering areas of interest. While this new philosophy has been adopted, as least in principle, by many engineering schools, the task of revising the cur- riculum has been a major challenge, particularly at the course level. The new electrical engineering curriculum calls for allocating fewer credit hours in many of the tra- ditionally core areas-electromagnetics (EM) among them. At many universities the required EM content of the program has been reduced from two courses down to one. For some, the intent is to continue to offer a two- course sequence, but with only the first being part of the required core and the second being for students interest- ed in deepening their knowledge in electromagnetics. Course Contents Given these objectives and associated boundary condi- tions, what then should be the contents of a one- semester or a two-course sequence in electromagnetics and what texts might one use for this purpose? To answer these questions, we should briefly review the traditional approaches that have been in use over the past two decades. Most EM books share a common tem- plate. They begin with one or more chapters on vector calculus and coordinate systems, followed by two or