Cost benefit analysis (CBA) determines the costs and benefits of a proposed project or policy. It has its origins in the 19th century and was established in US law in 1936. CBA is used to assess whether a project is economically feasible, which of multiple options provides the best return, and the optimal timing. It involves identifying costs like financial outlays and environmental impacts, and benefits like increased productivity or time savings. Alternatives are compared by weighing total benefits against total costs. CBA can be used to analyze options for reducing traffic congestion in Dubai by considering costs and benefits of policies, infrastructure projects, and public transport improvements.