Abstract: This paper uses a social model to investigate the complex area of identity in the British Army with special reference to the Infantry at unit level. The model, created in earlier research, specifically to examine unit-level organizational culture in the British Army, conceptualizes four different shared bodies of ideas, rules and conventions of behaviour which inform groups of people or individuals how to organize and conduct themselves vis-à-vis each other. Various axes of identity are described, based on these four 'social structures', revealing a multi-faceted and dynamic set of social issues. This investigation confirms that the model is a useful tool with which to examine issues of identity entirely within units of the British Army, but where these issues connect strongly with aspects or people outside the unit boundary it is a less appropriate tool. Even so, the model can be useful in providing insights into the origins of the elements that contribute to constructions by unit members of outsiders as 'the other'. This investigation implies that the model may be of use in systems engineering for British Army equipment projects (particularly with respect to the new Human Factors Integration Domain 'Organizational and Social'), and in planning organizational change in the British Army.