Globalization, technological change, economic crisis and an increasing demand for specialization have led to new economic activities, new business models and new value propositions. As enterprises try to react to these challenges, they realize that they need to transform through collaboration with other enterprises in business networks, in order to: a) develop new value propositions, b) reduce operating costs, and c) engage in value innovation activities. In order to enable this transformation, we propose a Service Science approach to assist enterprises in developing collaborative value propositions. Our two research objectives are: a) the design of a service system framework, b) the implementation of related tools for helping enterprises to engage in collaborative activities, while controlling transformation activities. Our framework is based on resource management and takes into account resource type (operant, operand), resource state (basic, composite, interconnected) and the constraints imposed by resource owners, in order to help firms co-create value propositions. Our framework can thus help enterprises appreciate what it means to take part in a business network (what resources they have to manage and how, what an enterprise can offer in a business network). Then we connect our framework to the well-known E3-value ontology to test our framework's effectiveness and to have a graphical representation of value flows scenarios generated by our framework.