As part of a move toward data-driven decision making, the University Libraries at Virginia Tech made a commitment to evaluate library instruction systematically. During the design and implementation phase of the program, library faculty developed a variety of tools for evaluating teaching, tested them out, and consulted with educational experts to review and improve those tools. The result of this process was greater understanding of the value of formative assessment and the adoption of a flexible approach that utilized a range of shared tools to address specific assessment needs.