Today's electronic design and test engineers deal with several types of subsystems, namely, digital, memory, and mixed-signal, each requiring different test and design for testability methods. This book provides a careful selection of essential topics on all three types of circuits. The outcome of testing is product quality, which means `meeting the user's needs at a minimum cost.' The book includes test economics and techniques for determining the defect level of VLSI chips. Besides being a textbook for a course on testing, it is a complete testability guide for an engineer working on any kind of electronic device or system or a system-on-a-chip.