The lack of believability of nowadays virtual characters may lead the users of Distributed Virtual Environments to stop using them, once the initial attraction of the innovation has declined. The successful use in the future of Distributed Virtual Environments for complex tasks, beyond simple chatting systems, might depend on our ability to provide the user with powerful virtual representations (avatars), which can be used not just as a presence indicator, but also as a tool to communicate with other users and establish interesting interactions. On the other hand, a very complex avatar, with many features and controls, can make it very difficult and tedious for the user to fully exploit the avatar’s possibilities. This paper presents a proposal for an internal model of avatars that allows the user to delegate some actions on an underlying intelligent agent. The main component of the model, the psychological model, is explained in detail. The use of the model is based on a fuzzy valuation and a definition of fuzzy relationships among the parameters. A dynamic updating process is also defined to maintain the internal state of the avatar. We have applied the model to an interesting game environment, where some of its most powerful characteristics are successfully exploited.