The peer-to-peer approach to design large-scale systems has significant benefits including scalability, low cost of ownership, robustness, and ability to provide site autonomy. However, this approach has several drawbacks as well including trust issues and lack of coordination and control among the peers. We present a trust model for a peer-to-peer structured large-scale network computing system and completely define the trust model and describe the schemes used in it. Central to the model is the idea of maintaining a recommender network that can be used to obtain references about a target domain. Simulation results indicate that the trust model is capable of building and maintaining trust and also identifying the bad domains.