Protecting critical industrial processes from attack has become a growing priority for many companies. Facilities have become more vulnerable as proprietary systems have evolved to open systems that use commercial technologies and, in turn, leave control systems exposed to the same viruses, worms and trojans that impact office environments. With both the number and the seriousness of security incidents on the rise, plant operators face increasing pressures to develop security programs for their plant, and equipment manufacturers need to meet growing customer demand for products that are "secure-by-design."