Existing mobile agent systems are often constructed with a focus on intelligence and autonomy issues. We have approached mobility from a different direction. The area of distributed systems research is quite mature, and has developed mechanisms for implementing a “sea of objects” abstraction. We have used this as our starting point, and added to this the ability for objects to move from host to host, whilst maintaining location-transparent references to each other. This provides a powerful and straight-forward programming paradigm which embraces programming language semantics such as strong typing, method invocation and encapsulation. We have built a Mobile Object Workbench on top of a flexible Java middleware platform, which can be used as a the basis for a Mobile Agent System. In this paper we examine the philosophy and design of the Mobile Object Workbench, and describe how this is being extended to provide a security framework oriented towards agents.