Sejong city is aimed at balancing regional development and easing overcrowding of the metropolitan Seoul by relocate many of governmental administrative offices in Korea. First Prime is the first residential project in Sejong City to develop as a symbolic and promotional sustainable residential community model. Thus "First Prime" was designed to ensure the harmony of human, nature and urban function. All buildings achieved highest grade on energy efficiency rating and admit many sustainable building design considerations including renewable energy, providing more than 40% of eco area, reservation of historical site, biomass retreatment system and link with sustainable transportation system. This project received highest grade on Korean green building rating.