The lived experiences of psychiatric inpatients are not well represented in the literature, especially when these experiences pertain to health. Reports regarding sleep health are particularly sparse, despite the increasing prevalence of sleep disorders in this population. The current study aimed to explore inpatient and staff perspectives of inpatient sleep quality to aid the future development of a sleep quality intervention. Fourteen inpatients (average age 43 years, 36 % female) were recruited for individual interviews and eleven staff members were recruited for three focus groups, from a secure psychiatric hospital (England). A semi-structured interview guide facilitated discussions regarding the prevalence and type of inpatient sleep problems, existing support for inpatient sleep problems including medication, and the bidirectional relationships between nighttime sleep and daytime behaviours, such as napping and physical activity. Using reflexive thematic analysis, four themes were developed: Irregular Sleep Schedules, Nighttime Disruptions, The Patient's Bedroom, and Keeping a Routine & Staying Physically Active. Study results can be utilised when developing inpatient sleep interventions, which were identified within the study as being sorely needed. Such interventions could focus on managing daytime sleeping, sedentary behaviour, and physical activity, in order to support good sleep hygiene, foster regular sleep/wake cycles, and improve overall health.