This is a critical time to understand the benefits and risks of educational research using large data sets. Massive quantities of educational data can now be stored, analyzed, and shared. State longitudinal data systems can track individual students from pre-K through college and work. Districts and schools keep detailed data on individual academic performance, behavior, and educational needs. Schools provide portals for parents to check student assignments and grades. Software developers and researchers collect data from applications used for instruction that include keystroke-level information about student decision making. The benefits of big data for educational research often arise when data sets are combined and merged. This summary report addresses a fundamental tension of how to reap the educational benefits that access to comprehensive "big" data provides while ensuring student privacy. In order to understand and improve teaching and learning, education data must be available to researchers, and the privacy of children and families must be protected. This report, based upon a workshop, reviewed the benefits of educational research using modern data systems, the risks to the privacy of families and children, and technical and political solutions for maximizing benefits and minimizing risks. In particular, the report recommends that the research community (1) adopt common terminology, (2) communicate the importance of educational research more effectively, (3) build strong partnerships and models to ensure the sharing of data, and (4) better educate researchers and universities on privacy issues. [The National Academy of Education (NAEd) held a two-day workshop on August 9-10, 2016, to address a fundamental tension faced by the education research community: how to balance the benefits of access to comprehensive ("big") data with the potential risks to privacy. The NAEd website contains a commissioned background paper, summaries of each workshop panel, handouts and presentations, and video recordings. https://naeducation.org/workshop-on-big-data-in-education-balancing-research-needs-and-student-privacy/.]