Technologies concerning computer-aided design, process planning, manufacturing and numerical control, have matured to a point that commercialized software solutions and industrial systems can be acquired readily. These solutions or systems are, however, not necessarily connected in a seamless way, that is they are not fiintegrated. The term “islands of automation” has been used to describe these disconnected groups of systems with no obvious integration points other than the end user. As the engineering businesses are increasingly being run in a more globalized fashion, these islands of automation need to be connected to better suit and serve the collaborative and distributed environment. It is evident that the businesses are struggling with this integration strategy at a number of levels other than the underlying technology, including CAD, CAPP, CAM, and CNC for example. In some cases, where integration does not exist among these computer-aided solutions, promising product technologies may come to a sudden halt against these barriers. The previous chapters have focused on these individual computer-aided solutions, e.g. CAD, CAPP, CAM, CNC, and feature technologies. Some localized integration such as integrated feature technology has been studied. The following chapters, will in particular, look at the integration issues, technologies, and solutions. This chapter starts with a general description of traditional CAD, CAPP, CAM, and CNC integration models. This is followed by an industry case study showcasing how a proprietary CAD/CAM can be used to achieve centralized integration. To illustrate CAM/CNC integration, three different efforts are mentioned. They are APT, BCL (Binary Cutter Location, (EIA/ANSI, 1992)), BNCL (Base Numerical Control Language, (Fortin, Chatelain & Rivest, 2004)) and use of Haskell language for CNC programming (Arroyo, Ochoa, Silva & Vidal, 2004).