A Safe System starts with quality data. Data-driven safety analysis (DDSA) is essential to making sound decisions on the safety, design, and operations of roadways for all road users. The Model Inventory of Roadway Elements Version 2.1 (MIRE 2.1) is the latest guideline resulting from two decades of Federal safety data policy and national best practices. The purpose of MIRE is to provide States with a national model of relevant roadway and traffic data inventory they can use to support data-driven decision making. Consistent with other MIRE updates, MIRE 2.1 includes a revised format to reflect modern database environments, better aligns with other Federal datasets and requirements across FHWA, updates operational and design elements that have become more widely implemented and serves as a resource for meeting Federal safety data requirements.