For many professors, testing is primarily a tool for assessing the learning of students. However, research into the "testing effect" has established the value of testing also as a learning tool, not just as an assessment tool. This article provides an overview of this research and also of my own experiences in using a variety of testing approaches. Based on these experiences, the article offers a process for adopting testing as a learning tool, along with a review of design choices. By increasing their use of testing in business law instruction, business law professors will improve learning.