This thesis presents a grounded theory of the flow experiences of Web users engaged in information-seeking activities. The term flow refers to a state of consciousness that is sometimes experienced by individuals who are deeply involved in an enjoyable activity. The experience is characterised by some common elements: a balance between the challenges of an activity and the skills required to meet those challenges; clear goals and feedback; concentration on the task at hand; a sense of control; a merging of action and awareness; a loss of self-consciousness; a distorted sense of time; and the autotelic experience.¶ Researchers have recently proposed Csikszentmihalyi's flow theory as a useful framework for understanding the enjoyment experienced by Web users, but they have struggled to operationalise key constructs such as flow and challenge in their quantitative models. This study aimed to address that problem by providing a better understanding of the nature of flow as experienced by Web users engaged in information-seeking activities. ...