In Search and Rescue (SAR) operations, the search team must know how to scan their search area efficiently with limited resources. Advances in mobile technology are driving the rapid growth of location based services (LBS) and this dissertation project investigates the feasibility of an LBS to support SAR operations. The LBS requires the ability to locate search team members, perform visibility analysis on-the-fly, and dynamically convey this information back to the user on a variety of mobile devices. The SARMApp (Search And Rescue Mapping Application) LBS is developed with the objective of providing proof of concept for such an application. SARMApp is implemented with a thin client architecture and the feasibility of visibility analysis for a single observation point, along with the feasibility of cumulative visibility analysis are investigated and performed to varying degrees of success. On the other hand, temporal cumulative visibility analysis is currently considered infeasible with the technologies investigated. The development and subsequent testing of SARMApp highlights a number of strengths and weaknesses in relation to geolocation performance , visibility analysis performance, the effectiveness of a web map and the usability of the user interface. It is concluded that SARMApp provides sufficient proof of concept that mobile technology could be used effectively to support SAR operations, however more work would be required if the application were to be used in a real-life SAR operation. In future it is anticipated that with further advances in technology, the envisaged SAR application will become more feasible and LBS could play a large role in SAR operations by increasing the efficiency of search operations and potentially saving lives as a result of this.