As unmanned platforms are more and more present in battlefield, alongside humans, in different configurations (from tele-operated to fully autonomous platforms, manned-unmanned teaming, swarming, etc.) and domains (space, air, land, sea, and underwater), it is also necessary for decision-making process to adapt to this new reality. This process will no longer be exclusively human and this requires that humans and machines share a common, meaningful, and timely understanding of the context in which they act and interact, namely a common situational awareness. We will investigate how this objective could be achieved by means of AI-related techniques of inference and reasoning based on ontologies that will enable all levels of information sharing (data, knowledge, and models) among all participants, humans and non-humans. The success of this undertaking shall be reflected by the achievement of a high level of interoperability between heterogeneous entities, within which they will be able to take advantage of each other’s best developed abilities.