From the observable climate change, global warming effect is truly alarming the world today. It has become a common concern for most of the countries to reduce the production of GHG nowadays. As many other high density cities, Hong Kong people are consuming a lot of energy and generating a significant amount of greenhouse gas (GHG) every year. According to the Hong Kong government’s data, there is about 42 million tons of GHG being produced in Hong Kong per annum (EPD, 2013). Among this significant sum, about 90% of the emission is created through the buildings. As a responsibility developed city, different kinds of construction techniques and management methods should be applied to reduce the creation of GHG. Besides inviting new technologies to reduce energy usage, educating the users and adopting proper management techniques are also important means to help reduce GHG making. Like Hong Kong’s nearby high density city Tokyo, it has been launching green activities with the IT (information technology) and ICT (information communication technology) industry namely “GreenIT/ICT” which not only focuses on the energy saving “of” the IT/ICT equipment but also on the energy saving “by” the IT/ICT technologies in the past decade (Yochida & Esaki, 2009). This paper will review how appropriate building technologies and management methods can help building practitioners and users to participate in building sustainable green development and improve the living environment.