Increasing numbers of schools and districts have expressed interest in interim assessment systems to prepare for summative assessments and to improve teaching and learning. However, with so many commercial interim assessments available, schools and districts are struggling to determine which interim assessment is most appropriate to their needs. Unfortunately, there is little research-based guidance to help schools and districts to make the right choice about how to spend their money. Because we realize the urgency of developing criteria that can describe or evaluate the quality of interim assessments, this article presents the results of an initial attempt to create an instrument that school and district educators could use to evaluate the quality and usefulness of the interim assessment. The instrument is designed for use by state and district leaders to help them select an appropriate interim assessment system for their needs, but it could also be used by test vendors looking to evaluate and improve their own systems and by researchers engaged in studies of interim assessment use. (Contains 14 tables and 4 footnotes.)