Research in carbon nanotubes has reached a horizon that is impacting a variety of fields, such as nanoelectronics, flat panel display, composite materials, sensors, nanodevices and novel instrumentation. The unique structures of the nanotubes result in numerous superior physical and chemical properties, such as the strongest mechanical strength and the highest thermal conductivity, room temperature ballistic quantum conductance, electromechanical coupling, and super surface functionality. Among the various analytical techniques, high-resolution transmission electron microscopy (HRTEM) has played a key role in the discovery and characterization of carbon nanotubes. It may be claimed that carbon nanotubes might not have been discovered without using HRTEM. There is a great need of a book that addresses specifically the theory, techniques and application of electron microscopy and associated techniques for nanotube research. The objective of this book is to fill this gap.