Despite the large body of research attesting to the advantages of the KWM, its utility and effectiveness have been ques- tioned on several occasions. For instance, Hall, Wilson, and Patterson (1981) show that free study can produce results superior to the KWM when applied to college students. Hall (1988) also argues that the KWM’sefficiency can be influenced by items’ characteristics, and cautions that, depending on circumstances of the study, the KWM can lead to poorer performances when it is used as the exclusive vocabulary learning method. Wang and Thomas (1995) indicate that, unless it benefits from repeated testing and rehearsals, the KWM becomes fragile over time and its long-term effectiveness can be questioned. Other studies (Hogben & Lawson, 1994; Van Hell & Mahn, 1997; Willerman & Melvin, 1979) indicate that the KWM can produce similar or inferior results compared with traditional learning methods (rote learning), and that experienced language learners benefit less from the KWM than the inexperienced learners. Some authors (Beaton et al., 2005; Wyra et al., 2007) help to explain the contradictory results by pointing out that critics have used different procedures, testing protocols, and item characteristics than the studies supporting the KWM