INTRODUCTION: Homelessness is rising in Ireland, and people experiencing homelessness face disproportionately poor mental health outcomes due to intersecting structural and psychosocial factors. Access to mental healthcare remains limited, leaving generalist services to manage increasing need, particularly during crises.

AIM: To explore healthcare professionals' experiences of managing mental health crisis episodes among people experiencing homelessness.

METHOD: A descriptive qualitative study informed by critical realism. We used semi-structured interviews with 14 healthcare professionals, including GPs, nurses, a psychotherapist, a hospital consultant, and service leaders. Reflexive Thematic Analysis was used to identify key patterns.

RESULTS: Five themes were identified: (1) barriers to accessing mental health services; (2) the role of trust and therapeutic relationships; (3) trauma-informed and holistic approaches to care; (4) the need for stability in housing, healthcare, and substance use; and (5) systemic and policy failures.

DISCUSSION: Generalist professionals are increasingly required to provide complex mental health support in a fragmented system that often excludes the most vulnerable.

LIMITATIONS: Findings reflect professional perspectives from a small sample and are not generalisable.

IMPLICATIONS: Trauma-informed, flexible, and integrated services are essential to support equitable care.

RECOMMENDATIONS: Develop inclusive, housing-linked mental health services that embrace harm reduction and reject rigid eligibility criteria.