The goal of this paper is to argue the need to approach the personalization issues in Web applications from the very beginning in the application's development cycle. Since personalization is a critical aspect in many popular domains such as e-commerce, it important enough that it should be dealt with through a design view, rather than only an implementation view (which discusses mechanisms, rather than design options). We present different scenarios of personalization covering most existing applications. Since our design approach is based on the Object-Oriented Hypermedia Design Method, we briefly introduce it, emphasizing the way in which we build Web application models as object-oriented views of conceptual models. We show how we specify personalized Web applications by refining views according to users' profiles or preferences; we show that an object-oriented approach allows maximizing reuse in these specifications. We discuss some implementation aspects and compare our ...