Abstract
In all international comparison studies, Japanese students, who were at the eighth and seventh grades in Junior high school, performed very well in mathematics. Researchers in mathematics education believe that one of the key reasons for this impressive achievement is the process of lesson study practiced by the Japanese teachers. Thus, the purpose of this paper is to describe what the Japanese lesson study is and then to examine the procedure in terms of how it is planned and conducted by Japanese teachers. The last part of the paper discusses whether teachers in Turkey should work collaboratively within the lesson study model to improve student learning, and in doing so enhance their own teaching practice.