The current edition of Video Microscopy has been totally revised to reflect the advances in the tools for electronic imaging, processing, recording, and analysis, as well as applications that are being made in video microscopy and related modes of electronic imaging. The less spiral organization of the revised edition reflects an audience expected to be more experi enced in video and computer image processing than in the earlier days when coupling of video equipment and computers to the light microscope was still considered to be a novelty. Nevertheless, we have emphasi2;ed the how-tos, as well as the fundamental principles, involved in imaging and processing ih the light microscope, the human visual system, video and related electronic imaging, and the digital image processor in the hope that the reader will develop enough understanding, not only to apply rationally what is available, but also to contribute actively to the development of this evolving field. In the text, the terms appearing in the Glossary are printed in bold type, generally, at first appearance. Italics are used for emphasis.