Database development is one of the fundamental objectives of the data management function and certainly one of the end products of the process. Several trends have impacted the way that databases are built and the role they play in the overall organization. Some of these trends include data warehousing, object-oriented technology, E-commerce, and the emergence of very large databases. The complexity that is inherent in constructing relational database solutions can be reduced by using proven database development methodologies on projects. Development methodologies with well-defined database development phases are commonly available in the marketplace. The chapter defines a high-level methodology for database development. This methodology provides a good start for small-to medium-sized projects; however, a formal third-party methodology should be considered for projects that require more than six months of development effort. It discusses some of the important deliverables that are created from inception to the creation of a physical database. Modeling tools are critical for the database development process.