The rise of the number and complexity of web applications is ever increasing. Web engineers need advanced development methods to build better systems and to maintain them in an easy way. Model-Driven Architecture (MDA) is an important trend in the software engineering field based on both models and its transformations to automatically generate code. This paper describes a a methodology for web application development, providing a process based on MDA which provides an effective engineering approach to reduce effort. It consists of defining models from metamodels at platform- independent and platform-specific levels, from which source code is automatically generated.