Maria Araceli Ruiz-Primo is an Associate Professor at the Graduate School of Education, Stanford University. Her work, funded mainly by the National Science Foundation and the Institute of Education Sciences, examines assessment practices and the assessment of student learning both in the classroom and in large-scale assessment programs. Her publications address the development and evaluation of multiple learning assessment strategies, including concept maps and students’ science notebooks, and the study of teachers’ informal and formal formative assessment practices, such as the use of assessment conversations and embedded assessments. She also has conducted research on the development and evaluation of assessments that are instructionally sensitive and instruments intended to measure teachers’ formative assessment practices. Recently she has worked on the analysis of state testing programs. She was co-editor of a special issue on assessment in the Journal of Research in Science Teaching and a special issue on classroom assessment in the Journal of Educational Measurement. She has published in Science, Educational Measurement: Issues and Practices, the Journal of Research in Science Teaching, and other major technical educational research journals.