Utilities, water districts, transportation agencies, airports, and many other businesses rely on industrial control systems (ICS) to automate and operate critical processes. ICS are easily integrated with business systems and can be implemented on a large scale to increase performance, reliability, and durability. Because ICS are essential to delivering and managing critical resources and infrastructure, they must be protected against cyber threats. Tampering with ICS can lead to dangerous consequences for human lives, a country’s critical infrastructure, and the environment.