Integrated circuits (IC's) have undergone a significant evolution in terms of complexity and performance as a result 'of the substantial advances made in manufacturing technology. Circuits, in their various mixed formats, can be made up tens or even hundreds of millions of devices. They work at extremely low voltages and switch at very high frequencies. Testing of circuits has become an essential process in IC manufacturing, in the effort to ensure that the manufactured components have the appropriate levels of quality. Along with the ongoing trend towards more advanced technology and circuit features, major testing challenges are continuously emerging. The use of ambivalent procedures to test the analogue and digital sections of such complex circuits without interfering in their nominal operation is clearly a critical part of today's technological ipdustries. Chapter 1 presents the general purposes and basic concepts rel~ted With' the"testing of integrated circuits, discussing the various strategies and their limitations. Readers who are already familiar with the field may opt to skip this chapter. This book offers a multidisciplinary focus on thermal testing. This is a testing method which is not only suitable for use in combination with other existing techniques, but is also backed by a wealth of knowledge and offers exciting opportunities in the form of as yet unexplored areas of research and innovation for industrial applications.