In Malaysia, the implementation of controls into an air conditioning system is still in the developing stage. However, the latest development shows that this implementation is growing rapidly. The rapid growth of this implementation is due to the efectiveness of the controls to improve the performance of teh air conditioning system and reduce the energy consumption of the equipments. The control systems are normally implemented into a new design of an air conditioning system. However, there are still a lot of air conditioning systems in the old buildings which even do not have any control system. Therefore, this project is carried out to study the concepts and philosophy of controls and the various types of air conditioning control systems which are being used and available in the market. A case study is carried out in this project to analyze the existing air conditioning control system of an ole coemercial building and improve the control system (in terms of energy saving, operating cost reduction and increase in efficiency) by proposing a more appropriate and efective control system. The energy, cost and efficiency analyses are also carried out to compare the performance and the economic aspect of both the existing and proposed control systems.