In this thesis I propose that the literature on ambidexterity does not fully explore the detailed practices by which organisations and managers may achieve both exploitation and exploration. A systematic review identifies that studies have focused principally at the organisation-level, and there is a lack of both empirical and theoretical work at the micro-level of analysis highlighting how ambidexterity may be achieved in practical, complex, working structures. The research addresses these micro-mechanisms in the context of the management of projects, a suitable area in that it can be considered as using defined processes together with the flexibility to overcome particular issues that arise. The contribution of the thesis is that it presents an insight into the management of ambidexterity in such an environment, and identifies how multiple knowledge resources are utilised, together with the underlying managerial practices. The level of analysis is the project (specifically, IT-services projects in a major multinational organisation), using the manager as the unit of analysis. The research question is ‘How is ambidexterity achieved at the level of the project?’ This is an opportunity to explore a practical as well as a theoretical gap, in an increasingly important area of business operations. The first stage of the research examines the managerial role in terms of intellectual capital, using a variety of projects. This shows that the sub-components of IC (human, social and organisational/project capital) can each be understood as having co-existing, orthogonal, exploitative and exploratory elements, an important extension of existing theory. The forms of intellectual capital are interwoven not only with each other, but also with the processes of exploitation and exploration, and to conceive of them as separate is an insufficient theorisation. The findings from the qualitative approach are used to investigate the duality of these concepts and bring greater clarity to our understanding of their operationalisation. .This is followed by eight case studies, each using between three and five managerial respondents, together with project data, used to develop a more fine-grained understanding of ambidexterity in a wide range of industrial settings. This shows different managerial configurations (including ‘distributed’ and ‘point’ ambidexterity – an addition to current theory), together with five key managerial practices to enable project-level ambidexterity, identified in the context of project complexity, critical events and constraints