Sketching web applications with mockup tools is a common practice that improves the process of elicitation and validation of requirements in web applications. However, mockups are used as a "quick and dirty" way of gathering requirements, thus discarded before development. As a consequence, concepts captured in them are usually lost in the manual transformation between mockups and the final user interface. In this paper we present a model-driven approach that overcomes this problem by importing mockups and then transforming them into a technology-dependent model. Development then begins from the imported version of the mockups.Publicado en <i>Lecture Notes in Computer Science</i> book series (LNCS, vol. 6385).Facultad de Informática