Background The philosophical perspective of a research methodology should explicitly underpin the decisions the researcher makes throughout the research. It is therefore important to understand the philosophical background and origins of Heideggerian phenomenology when using it as a research methodology.

Aim To discuss in detail the main philosophical ideas underpinning Heideggerian phenomenology.

Discussion Anxiety and boredom are two significant existential moods in Heideggerian phenomenology. Time is the basis of these moods and is an ‘originary temporality’. Originary temporality consists of a unified structure that includes the past, present and future. The experience of being human (‘dasein’) and its care/worry structure are significant features of originary temporality and consequently existential mood. Existential anxiety discloses the threefold characteristics of temporality to the individual, while existential boredom disrupts its unified structure. Both moods highlight the limits of existence to the individual and may culminate in additional distressing moods.

Conclusion It is essential for nurse researchers using Heideggerian phenomenology to understand the philosophical ideas underlining it.

Implications for practice The depiction of originary temporality and existential mood illustrated in this article could help nurse researchers embarking on a Heideggerian phenomenological study. The article could also inform researchers new to Heideggerian phenomenological research of the methodology’s philosophical background.