Delay is a quite common problem for construction projects. The existing practice of construction management is usually based on assessment of delays, liabilities and claims. However, this approach does not serve to remove the underlying causes of delay problems. In addition to estimation of delays, there is a need for a systematic method that will prevent delays in projects. Lean construction has tools and techniques that can serve for this purpose. However, a formal delay analysis procedure does not exist in lean practices since CPM adaptation is not well accepted. This paper advocates that integrated utilization of CPM and lean principles can help assessment of existing delays and minimization of delays in forthcoming stages. The methodology proposed in this study has not been applied on a real project, however, in this paper, its implementation steps are demonstrated using real project data. The proposed methodology is expected to help construction practitioners in delay analysis and when lean principles are applied appropriately, it can prevent delays, enhance schedule accuracy, and improve communication between the parties.