Background The unique characteristics of psychiatric institutions contribute to the onset and spread of infectious agents. Infection prevention and control (IPC) is essential to minimise transmission and manage outbreaks effectively. Despite abundant studies regarding IPC conducted in hospitals, to date only a few studies focused on mental health care settings. However, the general low compliance to IPC in psychiatric institutions is recognised as a serious concern. Therefore, this study aimed to assess perceived barriers and facilitators to IPC among professionals working at psychiatric institutions, and to identify recommendations reported by professionals to improve IPC. Methods A descriptive, qualitative study involving 16 semi-structured interviews was conducted (before COVID-19) among professionals from five Dutch psychiatric institutions. The interview guide and data analysis were informed by implementation science theories, and explored guideline, individual, interpersonal, organisational, and broader environment barriers and facilitators to IPC. Data was subjected to thematic analysis, using inductive and deductive approaches. This study followed the Consolidated criteria for Reporting Qualitative research (COREQ) guidelines. Results Our findings generated six main themes: (1) patients' non-compliance (strongly related to mental illness); (2) professionals' negative cognitions and attitude towards IPC and IPC knowledge deficits; (3) monitoring of IPC performance and mutual professional feedback; (4) social support from professional to patient; (5) organisational support and priority; and (6) financial and material resource limitations (related to financial arrangements regarding mental health services). The main recommendations reported by professionals included: (1) to increase awareness towards IPC among all staff members, by education and training, and the communication of formal agreements as institutional IPC protocols; (2) to make room for and facilitate IPC at the organisational level, by ...