Advances in automation and artificial intelligence, and especially in the area of intelligent (machine) agents, have enabled the formation of rather unique teams with human and machine members. This paper describes initial research into intelligent agents using a Beliefs-Desires-Intentions (BDI) architecture in a human-machine teaming environment. The potential for teaming applications of intelligent agent technologies based on cognitive principles will be examined. Intelligent agents using the BDI-reasoning model can be used to provide a situation awareness capability to a human-machine team dealing with a military hostile environment. The implementation described in this paper is using JACK agents and “Unreal Tournament” (UT). JACK is an intelligent agent platform while UT is a fast paced interactive game within a 3D-graphical environment. Each game is scenario based and displays the actions of a number of opponents engaged in adversarial roles. Opponents can be humans or agents interconnected via the UT games server. To support research goals, JACK extends the Bot-class of UT and its agents apply the BDI architecture to build situational awareness. This paper provides the background for the use of intelligent agents and their cognitive potential. The research is described in terms of the operational environment and the corresponding implementation that is suitable for intelligent agents to exhibit BDI behaviour. The JACK application will be described and specific requirements will be addressed to implement learning in intelligent agents. Other cognitive agent behaviour such as communication and teaming are aims of this research.