This document discusses trends in threats to SCADA (Supervisory Control and Data Acquisition) systems. It notes that as SCADA systems increasingly use commercial off-the-shelf software and connect to the internet, they have become more vulnerable to cyber threats. The document outlines how SCADA systems work and components like RTUs, PLCs, and HMIs. It also discusses issues like the mistaken belief that SCADA systems are secure due to physical security or isolation from the internet. The conclusion suggests that as capabilities and opportunities for threats increase, the future operational environment will be more vulnerable if an actor emerges with the intent to cause harm.