This article introduces the special issue, Using Mixed Methods to Advance Science and Practice in School Psychology. The goals of this special issue are to (a) provide conceptual, theoretical, and practical recommendations for increasing the use and quality of mixed methods research in school psychology and (b) feature studies that use a range of mixed methods designs and analyses. In this introduction, we assert that implementing high-quality mixed methods research can help our field solve urgent, complex problems in schools, yet mixed methods research remains underutilized. We summarize the articles featured in this special issue to help establish the merit of mixed methods research, and we close with a call for increasing the use of mixed methods research in school psychology by: (a) creating a pipeline of researchers trained in mixed methods, (b) bridging mixed method and school psychology research, and (c) increasing funding opportunities that support this research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).