Abstract: A system and method for preparing and optimizing a project plan is described. The system includes various modules including a database, a user interface, a cost analyzer, a resource conflict analyzer, a critical path analyzer, a calendar calculator, and a plan editor. The various analyzers and plan editor perform automatic calculations and analyses when preparing a project plan to optimize the project plan in terms of start and end dates, resource use and costs, and to reduce or eliminate errors in the project plan in terms of time conflicts and incorrect task dependencies.