Sensor Networks are heavily resource-constrained but nevertheless demand for generic flexible and efficient solutions to improve application development. By looking at the network as a collection of services, a user or a network node can use Service Discovery to browse locate and use the available services on the network. Moreover, Service Discovery besides enabling connection to external computer networks and interconnection between WSNs would simplify network self-organization and self-configuration. This paper proposes a simple solution for Service Support in WSNs based on Directed Diffusion. This paper addresses issues like efficiency, network interconnectivity, mobility and scalability. Preliminary simulation results show acceptable performance in distributed mode and point out the importance of good MAC and transport support.