Boston Scientific Korea participated to the activity to clean the stream “Yangjaecheon” which flows in front of Korea office. It was organized by AMCHAM Korea and BSK participated with the most, having the largest number of attendants among other company members. First, over 100 people from the each company member of AMCHAM met up and after the short opening we learned about the EM (Effective Microorganism) which is mixed into the clay is acknowledged as a catalyst to improve the quality of water, especially when mixed with a proper amount of fine clay. After that, we started to make the EM clay balls then threw them into the water. After finishing throwing the clay balls, we cleaned the stream by picking up trash, walking about 2.5Km along the stream and some employees went into the water to pick up trash in the stream.