Errors automating errors prevention error prevention automation and conflicts exist in many systems. A fundamental question from industries is How can errors and conflicts in systems be eliminated by automation, or can we at least use automation to minimize their damage? The purpose of this chapter is to illustrate a theoretical background and applications of how to automatically prevent errors and conflicts with various devices, technologies, methods, and systems. Eight key functions to prevent errors and conflicts are identified and their theoretical background and applications in both production and service are explained with examples. As systems and networks become larger and more complex, such as global enterprises and the Internet, error and conflict prognostics and prevention become more important and challenging; the focus is shifting from passive response to proactive prognostics and prevention. Additional theoretical developments and implementation efforts are needed to advance the prognostics and prevention of errors and conflicts in many real-world applications.