Mobile agents require access to computing resources on heterogeneous systems across the Internet. This demo illustrates how agents can negotiate terms and conditions of resource access with one or more mediators representing virtual organizations of autonomous hosts, before migrating to a new location. Time-limited resource contracts are the result: contracts between agents and mediators, and contracts between mediators and hosts. The negotiation protocol and language are based on the WS-Agreement Specification, and have been implemented and tested within the Agent- Scape framework. The demonstration shows in detail how this negotiation framework has been implemented for resource access on remote, distributed systems.