As information technology (IT) and information systems (IS) have become increasingly important in healthcare sector, researches have shown that the healthcare context is highly complex and the users in this context have many unique characteristics as compared to those in business contexts. These findings are scattered in the existing healthcare information systems (HIS) studies as “challenges” to and “deviations” from the classic IS acceptance theories; a holistic understanding of the HIS user’s lifeworld is yet to be achieved. Aimed at filling this gap, we conducted an empirical research in the clinical context informed by Heidegger’s phenomenology. Our purpose was to achieve a holistic understanding of the clinical users’ lifeworld and how they make sense of their encounters with HIS. Arguing against the Cartesian tradition in IS research, we developed an existential framework of IS users based on Heidegger’s concept of “Being-in-the-world” and used this framework as a conceptual instrument to inform our research design. By phenomenologically analysing the interview data with four doctors, we have illustrated how this existential framework can enable a holistic understanding of IS users’ lifeworld and their sense-making of their experiences with IS. We hope our exploratory work can inspire more empirical Heideggerian IS research endeavours.