This paper presents a distributed reputation and trust management framework that addresses the challenges of eliciting, evaluating and propagating reputation for web applications. We propose a broker framework where every user is associated with a reputation broker who collects for its users the reputation ratings about any web service. In return, a user provides its broker the service rating after each transaction with any service in order to build up the reputation for the service. In our mechanism design, brokers form a trust network where they exchange and collect reputation data about all services. By delegating trust management to brokers, individual users only need to check with their brokers about the reputation of a service before any transaction. We present the distributed reputation and trust management framework and show the performance of the system by simulations.