An important aspect of construction project management is site layout planning (SLP) which involves key decision making on aspects like location of tower cranes, location of inventories, parking spaces, temporary structures and understanding movement and co-ordination among various trades. SLP necessarily involves visualizing the progress of construction through the project and understanding the constraints and various processes involved. Such an activity would involve processing and visualizing complex information residing with different team members. Presently, this exercise is carried out using iterative exchange and understanding of information exchanged through paper documents and 2D drawings team meetings. Due to the complexity of the information to be processed, site layouts are decided usually based on past experience and seldom involves any optimization in planning. In the present work, we hypothesize that aiding the project team with an augmented reality based system in site layout planning would help better tap into the insights and experience of team partners and better achieve an optimized layout for the construction site. To this end, an extensive survey of the existing literature was done to understand the limitations and the dynamics involved in the SLP process now. Second, existing research on the use of technology including AR/VR in the field of planning was studied in detail. It is found that the use of BIM enabled frameworks in AR/VR systems would enhance and enable the incorporation of complex information in digital forms. Following this a BIM enabled Android based AR site layout planning tool was developed as part of this study. This tool uses marker based identification and tagging scheme to visualize the construction site. The tool incorporates a unique Genetic Algorithm based optimization of the site layout plan in terms of project cost based on the inputs from the users. An initial study of the user behavior while using this system compared to conventional systems point at the improved visualization of the site as compared to conventional process. It also indicates to the fact that the users faculties and experience are better employed more productively in the AR based system. Further, the focus was more of optimizing the layout than visualizing the project in the AR-based system which would further lead to better productivity. This preliminary results point out that AR based systems could be extremely useful in achieving optimized and well thought out site layout schemes as compared to traditional planning systems. Further development of the tool, experiments to study the planning processes involved in AR based systems are required to improve overall construction site layout planning.