BACKGROUND: End-of-life discussions often are not initiated until close to death, even in the presence of life-limiting illness or frailty. Previous research shows that doctors may not explicitly verbalize approaching end-of-life in the foreseeable future, despite shifting their focus to comfort care. This may limit patients' opportunity to receive information and plan for the future. General Practitioners (GPs) have a key role in caring for increasing numbers of patients approaching end-of-life. OBJECTIVE: To explore GPs' thought processes when deciding whether to initiate end-of-life discussions. METHODS: A qualitative approach was used. We purposively recruited 15 GPs or GP trainees from South-East Queensland, Australia, and each participated in a semi-structured interview. Transcripts were analyzed using inductive thematic analysis. RESULTS: Australian GPs believe they have a responsibility to initiate end-of-life conversations, and identify several triggers to do so. Some also describe caution in raising this sensitive topic, related to patient, family, cultural and personal factors. CONCLUSIONS: These findings enable the development of approaches to support GPs to initiate end-of-life discussions that are cognizant both of GPs' sense of responsibility for these discussions, and factors that may contribute to caution initiating them, such as anticipated patient response, cultural considerations, societal taboos, family dynamics and personal challenges to doctors.