Edited by Patricia Alexander (University of Maryland), Felice J. Levine (AERA), and William Tate (Washington University in St. Louis), this centennial volume of RRE takes a "retrospective, prospective" approach on a diverse range of education research topics spanning the last 100 years. While using historical trends as foundations for their chapters, the authors also look ahead to the most challenging issues and promising directions for the next century. The chapters contribute to cumulative knowledge, capture research developments and findings of sustained significance, and address research innovations anchored in their time or place, which could ultimately shape directions of scholarly promise and potential for the future. To bring conceptual cohesion to the volume, the editors nested the chapters in four thematic sections: (1) the Research Enterprise and the Doing of Education Research, (2) the Contexts of Education, (3) the Process of and Substance of Learning, (4) and the Changing Attention to Diversity and Difference.