Time Sensitive Targeting is a microcosm of military operations that employs the full range of resources in order to efficiently detect, identify, target, engage and assess emerging targets in the Area of Responsibility. Due to the high importance assigned to Time Sensitive Targets and the normally very compressed timelines involved in successfully engaging them, a computer-based tool to support access to critical data and the exchange of information between personnel participating in the Time Sensitive Targeting process is essential. The Flexible, Advanced C2 Services for NATO (Joint) Time Sensitive Targeting (FAST) tool has been implemented to provide these capabilities as a coordination and collaboration tool, designed to aid in the tracking and prosecuting of Time Sensitive Targets. The FAST tool provides user level authentication and authorisation in terms of security. It utilizes operating system level security but does not provide application level security for the stored and communicated data between participants. It would be better to enhance the security of the FAST tool in terms of data and communication. This paper illustrates how the security enhancement for the FAST tool can be achieved from a theoretical perspective.