21st Century Game Design teaches designers how to design better games, not from a how-to perspective, but from a why perspective. Good designers know the fundamentals of how to design a game, but learning how to study and understand their intended audience helps make games that truly satisfy players. Understanding the players? needs also provides the missing link between the process of design and the players, developers, and publishers of games. By applying psychological metrics to survey data and case studies, a framework was produced which identifies some of the core themes in player needs and is represented by four player types - Conqueror, Manager, Wanderer, and Participant. In addition to discussing how a game reaches a wider audience by appealing to the core gaming community, the book considers the fundamental principles of game design. Methods such as interface design, structural elements, and game world abstractions are discussed in relation to the needs of the audience.