Appropriate planning of a project is the hallmark of a professional project manager. Good planning is what sets apart great projects from accidents. Purposeful planning is what ensures that the executive actions undertaken remain connected to the goals and outcomes expected by the stakeholders. There is no single approach to planning a project, but neither is project planning a free-for-all. This book takes you through many of the common planning situations you will meet, addressing how planning decisions alter depending on the project context. It also discusses how resource-constrained planning differs from end-date schedule planning. The authors look at what is different between cost-constrained plans and time boxing and they discuss why you must plan when using Agile, and how to plan for innovation, as well as planning when managing a project portfolio, and what planning means in a program. To tell this story, we have distilled over seventy years of our combined personal experience of supporting project managers deliver, and thousands of person-years of others' practical knowledge to illustrate tools, models, and approaches that suggest what to do in what circumstances. Also available are supplementary materials and tools, on a website associated with the book, which we hope you find useful when you plan your next project!