Based on quality function deployment (QFD), we develop a simple, intuitive method, formulated as constrained non-linear programming for managing product development for obtaining the best quality product under dynamic resource constraints. The model can respond to changes in the environment including changes in customers' desires, introduction of new technologies, reduction of budget, or changes in the company workforce. Our model improves existing models by incorporating realistic cost functions and allowing its continuous use throughout the project. While using QFD, we also extend the original technique to remove a shortcoming in the roof of the house of quality (HoQ). We give a criterion for guaranteeing global optimality and briefly describe the use of the method in a real project.
