The What Works Clearinghouse (WWC) considers information provided about a study's context, sample, design, analysis, and findings when evaluating a study using the WWC regression discontinuity design standards. This document provides guidance to study authors about how to describe regression discontinuity design studies and report their findings in a way that is clear, complete, and transparent. The first two sections detail the descriptive information, and the third section describes the data that WWC reviewers use to assess studies. The fourth and final section details the additional descriptive information that WWC reviewers use to assess regression discontinuity design studies with multiple, pooled, or aggregated impacts. This document does not include information about how studies are judged against WWC design standards.