INTRODUCTION: Prevention of suicidal behaviour is complex, and a host of effective interventions have now been recognised in addressing this concern. However, adoption, delivery, and sustainment of these interventions within real-life settings is challenging
and the translation process, often overlooked. Examining the impact of context is necessary to explain how implementation outcomes are achieved and aid generalisability of findings. This study aims to explore factors influencing implementation outcomes (contextual determinants) across the implementation lifecycle of complex suicide prevention interventions. METHODS: A qualitative design was adopted. Semi structured interviews were conducted with 16 stakeholders (leaders, project managers/implementors, lived experience advocates) involved in implementation of complex suicide prevention interventions across the world. A purposive and snowball sampling approach was used to identify participants with requisite experiences. An understanding of determinants was deduced from participant narratives. These were mapped using the Exploration, Preparation, Implementation and Sustainment (EPIS) framework. RESULTS: Across different phases of implementation, outer context barriers were predominantly reported and pertained to service environmental factors, pre-existing dynamics, and engaging leadership. Several inner context barriers including individual characteristics, staffing and resources, and challenges in maintaining fidelity were reported during the implementation phase. Bridging factors (such as interrelationships and partnerships) were identified as important facilitators throughout different phases of implementation and levels of context. Implementation strategies related to stakeholder relationship building were prioritised across different phases of implementation. CONCLUSION: This study helps expand the notion of an evidence-base for complex suicide prevention interventions. Determinants salient across different levels of the social-ecology and phases of implementation address questions related to what works and under what circumstances.