Libraries are continually changing to meet the needs of users; this includes implementing discovery tools, also referred to as web-scale discovery tools, to make searching library resources easier. Because these tools are so new, it is difficult to establish definitive best practices for teaching these tools; however, promising practices are emerging. A promising practice is "a program, activity, or strategy" that shows early promise for being effective in the long term and generalizable across institutions (Dare Mighty Things, n.d.). The researchers used three methods to develop a list of promising practices for teaching discovery tools--a review of the current literature on the tools, a survey for practicing instruction librarians, and interviews with teaching librarians. More research and assessment is needed to determine whether these promising practices are in fact best practices for teaching discovery tools.