VLSI ( Very Large Scale Integration ) Design activities is key behind successful introduction of many of the new products. VLSI Design activity has shown compounded annual growth of over 20%. However success rate of VLSI Design has been challenged by factors such as reduction in geometrical features, integration of analog, digital and RF functional modules. VLSI Circuit Edit technology is the only promising solution to provide technological solution in confirming and validating flaws related to VLSI Design. The book provides brief description of Focused Ion Beam system and its accessories through which circuit edit technology is implemented. Methodologies for VLSI Circuit Edit have been described. This include Decapsulation of IC, Polyimide removal, Metal cutting, metal deposition, etc. Some of the novel techniques developed for VLSI Circuit Edit technology have been described. The book also indicates various new challenges in the domain. These challenges need to be addressed in future to evolve and provide solutions to the VLSI Circuit Edit. Semiconductor industries can survive and grow only with successful implementation of VLSI Circuit Edit technology.