The development of effective educational software requires a systematic process executed by a skilled development team. This article describes the core skills required of the development team members for the six phases of successful educational software development. During analysis, the foundation of product development is laid including defining the audience and program goals, determining hardware and software constraints, identifying content resources, and developing management tools. The design phase creates the specifications that describe the user interface, the sequence of events, and the details of the content to be displayed. During development, the pieces of the educational program are assembled. Graphics and other media are created, video and audio scripts written and recorded, the program code created, and support documentation produced. Extensive testing by the development team (alpha testing) and with students (beta testing) is conducted. Carefully planned implementation is most likely to result in a flawless delivery of the educational software and maintenance ensures up-to-date content and software. Due to the importance of the sixth phase, evaluation, we have written a companion article on it that follows this one. The development of a CD-ROM product is described including the development team, a detailed description of the development phases, and the lessons learned from the project.