Due to the increasing density of population and high cost of land in urban areas, especially in Addis Ababa, the architecture of commercial and residential buildings is evolving towards high rise structures. However, several studies show that many of these projects suffer from delay and cost overrun.rnPlanning and control of time are essential for successful completion of such high rise building construction projects. Bar charts together with network techniques are commonly used for communicating project schedules, however, such methods produce a huge complex network difficult to visualize and understand for the majority of construction personnel. This also discourages execution personnel from updating and using the schedule for progress monitoring.rnThe purpose of this research is thus to devise a scheduling system for high rise building construction by combining the advantages of critical path method and matrix scheduling technique and making some improvements to these methods. Matrix schedules are an efficient way to present information regarding repetitive projects but lack the analytic qualities of the critical path method. A study of planning and scheduling was performed and a system was developed and implemented as a software application.rnThe developed software was tested through three actual high rise building projects. The system adds a spatial dimension to the scheduling process which makes it easy to better present the plan of action and communicate the plan to everyone involved with the project. Other features include correction of duration to account for the influence of bad weather and maintaining continuity of repetitive activities. These features help to produce a realistic schedule for such repetitive projects.