Green Architecture integrates various durable solutions to the buildings for a durable relationship of built environment and nature. In order to maximize eco-friendliness and the effect of energy reduction, Green Architecture goes through simulation analysis, reports, and certifications from the early stage to completion to materialize green buildings with optimum quality. At the stage of design, it suggests guidelines and design alternatives for a passive design and also suggests renewable energy and equipment system for energy-saving designs. In addition, Green Architecture carries out various energy simulations and environment quality evaluations on light, noise, heat, atmosphere, etc. at its planning stage, and also certification work for green architecture and preparing reports for energy saving.