Abstract: This paper describes the "Requirements-Based UML" (RBU) development technique. RBU is a straightforward, pragmatic methodology for integrating structured requirements analysis into an UML-based analysis and design effort. This approach involves a high degree of customer participation and the creation of measurable requirement definitions before each stage of modeling and/or coding. RBU includes only the essential tasks and is designed to be highly communicative and easily understood by customers and professional development staff. Most often developed in cooperation with customers via "Joint Application Design" (JAD) approach, requirements are used to design and validate the application functionality. This paper does not present a complete implementation guide for a professional development organization. It describes RBU's major tasks and techniques, but does not include all of the necessary components of a robust methodology (e.g., standards, procedures, forms, etc.).