The PDRI (Project Definition Rating Index) is a tool that rates the completeness of project scope definitions for building projects. It identifies critical scope definition elements and allows teams to predict risks. The PDRI provides benefits such as standardized terminology, a checklist for defining scope, and a means to monitor scope progress. It is intended to evaluate scope definition before construction documents and can be used by anyone wanting to improve project performance, including designers, constructors, and all project participants.