Project planning guidelines are a set of rules and regulations that govern the process of project planning. These guidelines are designed to ensure that projects are planned and executed in an efficient and effective manner. They are used to provide a framework for project planning and to ensure that all stakeholders are aware of the goals and objectives of the project. Project planning guidelines can also help to ensure that projects are completed on time and within budget. They provide a common language for project planning and help to ensure that all stakeholders are on the same page. Additionally, they can help to ensure that the project is well-structured and that the team is able to work together in a cohesive manner. Ultimately, project planning guidelines help to ensure that projects are successful and that they are completed in a timely and cost-effective manner.