Problem statement: Wireless Sensor Networks (WSN) has become a very interesting field of research and has been deployed for various applications. The data sensed by the sensors need to be transmitted over to a Base Station (BS) where the data processing is done. Approach: The existing systems generally employ Multi-hop routing for data aggregation at the BS, where several nodes may forward data packets to the BS. This will lead to the reduced lifetime of the network and reduced battery life for sensor nodes near the BS, as they have to relay data from all parts of the network to the BS. Results: A simple yet efficient method to improve the network lifetime is designed with the help of Mobile Element (ME). The MEs act as mechanical carriers which move around in the sensing field, collecting the data from the sensors and transmitting them to the BS. In a relatively larger network, a single mobile element might not serve the purpose. So Rendezvous Points (RP) can be used in the network, to enhance the performance of the WSN. Conclusion/Recommendations: This article discusses the state of the art and major research challenges in scheduling these ME and the arising need for multiple MEs also being outlined.