Industrial environments and critical infrastructure often have different types of computing equipment, a wide array of manufacturers, different communications protocols, physical access controls, and stringent regulatory compliance requirements compared to general purpose or "office" environments. Operational Technology (OT) and Critical Infrastructure ecosystems also have requirements for high security and sometimes face different types of threats. In this session, we'll consider how OT and ICS environments differ from regular IT, the challenges they face in securing their assets, as well as technical approaches to providing layered security for OT and ICS.