The development of a cost baseline and a cost management plan is part of the planning process group of project management. To create these, you must first define the scope and work breakdown structure (WBS) of the project, which provide the basis for estimating and budgeting costs. Afterwards, you can estimate costs using analogous, parametric, bottom-up, or three-point estimating methods. You may also use historical data, expert judgment, or market research to support your estimates. Next, you need to determine the budget by aggregating the estimated costs of the work packages and activities and adding any contingency reserves and management reserves. This budget represents the total authorized cost of the project. Afterward, you must establish the cost baseline by approving and documenting the time-phased budget for the project without any management reserves. This cost baseline is used for measuring and controlling project costs. Finally, you should develop a cost management plan by defining and documenting processes, roles, responsibilities, tools, techniques, and standards for managing project costs. This plan should be aligned with the project management plan and other subsidiary plans.