Vertical transportation is essential for high rise buildings. An efficient lift system should have minimum waiting time at any floor level, rapid transportation time to the desired destination, passenger comfort in the lift and lesser travelling distance to reduce the energy and extend equipment life. There have been a number of control algorithms developed to improve the quality of the lift system. There are many factors involved in the analysis of the lift control system. This report describes the various required parameters affecting the performance of a lift control system and proposes a control algorithm for lift group control system. Our algorithm is developed in a general setting to optimize the efficiency of lifts in buildings such as reduced waiting times for lift passengers on each landing and other associated factors. A software package called CALCSS (Computer Aided Lift Control System Simulation), written in Visual Basic language, has been developed to compare the conventional method with our optimal method in lift efficiency optimization. Master of Science (Computer Control and Automation)