Since the mainstream uptake of computers and the internet, our world has become increasingly virtualised. Modern organisations are deeply reliant on virtual technologies to carry out their business across time and distance. Indeed, virtual technologies are now implicated in almost all organisational activities, from (virtual) meetings to (online) collaboration. Many scholars have been drawn to investigate the new organisational phenomena that have resulted from the virtualisation of our world, such a virtual learning, virtual leadership and virtual decision making. My research, however, tackles a more fundamental question about how organising more generally is accomplished in the virtual age. Namely, the research question is, “How does sensemaking, as the basis of organising, take place in virtual settings?” To explain, sensemaking – a foundational concept in Organisation Studies – underpins all organisational activities. Therefore understanding how sensemaking takes place in virtual settings will necessarily illuminate how organising more generally is accomplished virtually. To date, how sensemaking takes place in virtual settings has hardly been studied. Further, the studies that do exist impose Weick’s (1969, 1979, 1995) theory of sensemaking (which was developed at a time pre-dating virtual technologies) on to the new context. As a result, existing studies do not illuminate what is new, unique and interesting about how we make sense in virtual settings. In this thesis I develop an alternative, practice-based conception of sensemaking (which serves as the theoretical framework for the study) that sensitises me to previously overlooked but critical concepts, namely materiality, embodiment and ongoing accomplishment. First, materiality describes how things, which in virtual settings are often digital, are implicated in sensemaking. Second, embodiment describes how physical bodies, and their digital representations in virtual settings, are involved in accomplishment of activities. Finally, ongoing accomplishment describes how sensemaking takes place in the flow of activities as they are carried out in the physical world, the virtual world, or combination of both. This framework also enables me to position activities as the unit of analysis for sensemaking. Taken together, this is a novel approach that reveals new facets of the phenomenon of sensemaking in virtual settings. This theoretical framework is applied in three different fieldsites (of varying levels of virtuality) which are selected using a virtuality continuum developed within the thesis. These fieldsites are Yammer (a social media platform), telepresence (a video-based collaboration platform), and Second Life (a three-dimensional virtual world). The methodology is a hybrid traditional-virtual ethnography in which data is collected through participant observation, complemented by interviews. Empirical data are presented in the form of accounts that exemplify the key activities of practitioners in each fieldsite. The analysis reveals how sensemaking is enabled, constrained and altered owing to activities being carried out virtually (rather than in traditional settings). Further, various unique features of sensemaking as it takes place in each fieldsite are articulated, which become the subject of a cross-fieldsite comparison. By overlaying the results from each fieldsite on to the virtuality continuum, the question of how sensemaking takes place in virtual settings is answered in two ways. First, features of sensemaking that are common across all fieldsites, and therefore levels of virtuality, are identified. Second, I identify features of sensemaking that are specific to particular fieldsites and make inferences about how sensemaking features change depending on the level of virtuality of the setting. Some anomalies arising from this analysis are resolved by suggesting an alternative matrix model of virtuality which has potential to be included in future research. The findings culminate in articulation of a practice-based theoretical account of “virtual sensemaking”. This virtual sensemaking is then compared to traditional sensemaking, further illuminating the uniqueness of how sensemaking takes place in virtual settings. I then articulate contributions to the fields of sensemaking and organising as follows. This is the first study to articulate an account of sensemaking as it takes place specifically in virtual settings. Moreover, the account of virtual sensemaking broadens our understanding of sensemaking generally by opening up previously under-theorised aspects of how we accomplish (virtual) organisational activities. Contributions to broader organising include reconsideration of how we define quintessential organising activities, such as meetings. Practical implications pertain to creators, administrators and users of virtual technologies who may use this knowledge of virtual sensemaking to inform more effective and efficient design, implementation, management and application of virtual technologies in organisations. Finally, exciting avenues for future research are suggested, including opportunities to reconceptualise the theoretical, empirical and analytical landscape for investigating organising in the modern virtual age. Namely, we may let go of notions of organising that are rooted in traditional settings and embrace new conceptions of virtual organising. Organising is no longer place-specific or linear, nor does it require our physical presence or real-time participation. Instead, modern virtual organising is a complex, multi-dimensional blending of the physical and virtual. As technologies evolve and our activities become ever more integrated with them, understanding how we achieve this blending will be paramount to progressing the field of Organisation Studies generally.