In 1991 this author published a monograph[l] based on his experience teaching microwave hybrid materials and processing technology at the annual ISHM (now the International Microelectronics and Packaging Society, IMAPS) symposia. Since that time, the course has been presented at that venue and on-site at a number of industrial and government organizations. The course has been continually revised to reflect the many evolutionary changes in materials and processes. Microwave technology has existed for almost 175 years. It was only after the invention of the klystron, just before World War II, that microwave design and manufacture moved from a few visionaries to the growth the industry sees today. Over the last decade alone there have been exploding applications for all types of high frequency electronics in the miltary, automotive, wireless, computer, telecommunications and medical industries. These have placed demands, unimaginable a decade ago, on designs, materials, processes and equipment to meet the ever expanding requirements for increasingly reliable, smaller, faster and lower cost circuits.