Twenty-five years have passed since a teaching technique, called shadowing, was introduced in Japanese EFL contexts. Recently, this technique has gradually been recognized around the world. Given that many studies have been published about shadowing, the time is ripe to summarize the results of the studies and to propose how shadowing should be used. This article introduces shadowing, first referring to theoretical explanations provided so far, especially in terms of attention, cognitive process, and listening process.The article then summarizes past studies on the effects of shadowing on listening and speaking. Next, it discusses challenges in research and also introduces shadowing variations for further use of shadowing. As a classroom teaching tool, this article suggests that beginner level learners should start from shadowing for listening and proceed to shadowing for speaking.