This paper puts forward an integrated framework for proactive and optimal decision making on projects adopting a process simulation approach. Upstream decisions on project selection and scope definition are linked with the downstream operational processes and service delivery of projects. The findings presented in this paper are based on a case study conducted on a tram route redevelopment project in Melbourne. The research adopted the simulation modelling to determine the vehicle queue lengths, delays and traffic flows without utilizing numerical analysis across the signalised road traffic junctions. Based on the traffic flow condition and external uncertainties associated with the operating environment, a number of feasible designs and configuration of the project options has been developed. The project life cycle objective functions are then employed as the basis for decision making to determine the optimised solution throughout the project's life.