This paper presents an agent-based approach to Network Intrusion Prevention on corporate networks, emphasizing the protection from fast-spreading mobile malicious code outbreaks (e.g. worms) and related threats. Agents are not only used as a system-integration platform, but we use modern agent approaches to trust modeling and distributed task allocation to efficiently detect and also counter the attack by automatically created and deployed filters. The ability of the system to react autonomously, without direct human supervision, is crucial in countering the fast-spreading worms, that employ efficient scanning strategies to immediately spread farther once they infect a single host in the network.1