In school districts across the nation, diverse student groups, including English Learners and students with disabilities, have been experiencing significant gains in reading performance after using READ 180. This compendium of READ 180 research contains results of 40 studies conducted in a variety of settings, in school districts across the country from 2000 to 2015. Studies include randomized control trials, quasi-experimental studies, as well as correlational and descriptive studies. Results on reading gains for the general student population and in some cases for specific demographic groups of students are provided. The studies in this compendium show that READ 180 meets the literacy needs of even the most challenged students, and the findings of these studies have been integral in informing new and better versions of the program, including the most recent READ 180 Universal. An index is included. [This document has been revised-rebranded by Houghton Mifflin Harcourt to supplement the "Compendium of Read 180® Research: 15 Years of Evidence-Based Results for America's Struggling Readers" (ED562683).]