The IADC HSE Case Guidelines for Land Drilling Units were written to provide the worldwide onshore drilling industry a tool to harmonize global health, safety and environmental principles applicable to drilling units into a single methodology. This framework assists regulatory bodies, drilling contractors, and oil and gas producers improve personnel safety and environmental protection worldwide. Industry and regulators alike have embraced the Guidelines. Content includes an introduction to the HSE Case, HSE management for drilling contractors, rig description, risk management, emergency response and performance monitoring. Three appendices, plus access to one evergreen online appendix.