Projects have existed since the earliest agrarian societies. While they may differ in purpose, scale, and scope, each project is established to bring together people with diverse knowledge to complete a temporary assignment, solve a complex problem, or turn a novel idea into reality. The Introduction defines a project as a combination of people and other resources brought together in a temporary organization and process to achieve a specified goal. It considers the role of the project manager, the difference between projects and operations, and a brief history of projects. Traditionally, project performance has been measured by the three constraints of cost, time, and quality, but it is now recognized that project success is multidimensional and varies over time.