AASHTO GDHS-7, A Policy on Geometric Design of Highways and Streets, Seventh Edition (2018), commonly known as the Green Book, presents the current design policy for highway and street geometric design. Chapter 1 sets out a new framework for geometric design, followed by chapters on design controls and criteria, elements of design, and cross-section elements. The remaining chapters address design by facility category, covering local roads and streets, collector roads and streets, and arterial roads and streets. Separate chapters then treat freeways, intersections, and grade separations and interchanges. The framework is more flexible, multimodal, and performance-based than earlier editions, so a designer can fit solutions to the surrounding context rather than to a single fixed standard. The policy is intended for highway engineers and designers in state and local agencies, and for consultants preparing designs for those agencies.