The Center on Standards, Alignment, Instruction, and Learning (C-SAIL) examines how college- and career-readiness (CCR) standards are implemented, whether they improve student learning, and what instructional tools measure and support their implementation. Established in July 2015 and funded by the Institute of Education Sciences (IES) of the U.S. Department of Education, C-SAIL has partnered with California, Kentucky, Massachusetts, Ohio, and Texas to explore their experiences with CCR standards-based reform, particularly with regard to students with disabilities (SWDs) and English language learners (ELLs). This report examines how the state of Massachusetts is approaching CCR standards implementation during a time of transition, as it develops the Next-Generation Massachusetts Comprehensive Assessment System, or the "Next-Gen MCAS," in 2015-2016. The transition will take place in 2016-2017, with full implementation of the next-generation assessment by the spring of 2017. For the purposes of this report and in keeping with C-SAIL's focus, the authors concentrate on implementation of Massachusetts' English language arts (ELA) and math standards. Drawing on interviews with four key state officials across various offices of the Massachusetts Department of Education, the report synthesizes and analyzes those responses using the "policy attributes theory" (Porter, Floden, Freeman, Schmidt, & Schwille, 1988), a theoretical framework positing five attributes related to successful policy implementation (specificity, authority, consistency, power, and stability). The report focuses on five focal areas--standards and curriculum, assessment, professional development (PD), English language learners (ELLs), and students with disabilities (SWDs). The authors report on each focal area through the lens of the policy attributes to help readers see how state officials identified areas of strengths and challenges related to standards implementation in Massachusetts. [This report was written with Nelson Flores, Katie Pak, Amy Stornaiuolo, and Laura Desimone.]