RwD crashes account for 87 percent of curve-related fatal crashes. While the majority of these involve vehicles leaving the roadway and striking roadside objects such as trees and guardrail, about 10 percent of them are head-on crashes where vehicles wander across the center line of a curve and into the opposing lanes. The majority of roadway departure crashes are preventable, but it takes attention and knowledge to avoid them. This Flyer provides a brief overview the importance of understanding the advance message provided by signs and markings and the approach new drivers as they approach a horizontal curve. FHWA-SA-21-091