Information sharing is increasingly recognized as the most essential requirement for success in modern military and civil-military coalitions. Coalition operations consist of information systems characterized by highly dynamic and information rich environments, large varieties of information technologies deployed, and great diversities of individuals involved. Although all of these individuals have to ’share to win’, extensive information sharing still appears to be the exception rather than the rule. Individuals tend to hoard information for various reasons. Extant research explored individual information sharing behaviour and the use of information technologies for sharing from various perspectives. This paper emphasizes the need for a multidimensional conceptualization of individual information sharing behaviour by integrating different perspectives. I argue that an individual’s decision to engage in information sharing is determined jointly by a cognitive, a social-psychological, and a technological dimension, and label these dimensions Identification, Inter-relation, and Interchange, respectively. I employ two multiple qualitative case studies involving data from realworld information sharing drawn from the military domain to develop a multidimensional model for the assessment of individual information sharing behaviour. The proposed model enables a systematic identification of this highly complex and challenging process. This identification is a first step in assessing the multifaceted phenomenon of information sharing in complex socio-technical systems. Implications for theory and practice are discussed, and future research directions are proposed.