Background:Delirium is a distressing condition often experienced by hospice in-patients. Increased understanding of current multidisciplinary care of delirium is needed to develop interventions in this setting.Aim(s):To explore hospice staff and volunteers’ practice, its influences and what may need to change to improve hospice delirium care.Design:Qualitative interview study using behaviour change theory from a critical realist stance.Setting/participants:Thirty-seven staff, including different professional groups and roles, and volunteers were purposively sampled from two in-patient hospices.Results:We found that participants’ practice focus was on managing hyperactive symptoms of delirium, through medication use and non-pharmacological strategies. Delirium prevention, early recognition and hypoactive delirium received less attention. Our theoretically-informed analysis identified this focus was influenced by staff and volunteers’ emotional responses to the distress associated with hyperactive symptoms of delirium as well as understanding of delirium prevention, recognition and care, which varied between staff groups. Non-pharmacological delirium management was supported by adequate staffing levels, supportive team working and a culture of person-centred and family-centred care, although behaviours that disrupted the calm hospice environment challenged this.Conclusions:Our findings can inform hospice-tailored behaviour change interventions that develop a shared team understanding and engage staff’s emotional responses to improve delirium care. Reflective learning opportunities are needed that increase understanding of the potential to reduce patient distress through prevention and early recognition of delirium, as well as person-centred management. Organisational support for adequate, flexible staffing levels and supportive team working is required to support person-centred delirium care.