Service mobility is a highly desirable feature of future networks and will be a key factor in supporting mobile users and meeting the increasing demand for service resiliency and efficient resource management. Currently the main approaches for developing mobile services are active capsules and mobile agents but these are limited by design and fail to deliver sufficiently generic and broadly scoped solutions. In this paper we propose a framework for developing mobile (active) network services that aim to provide a more generic functionality over that offered by current approaches, promoting a more flexible and intuitive way of developing mobile applications.