Medicines management is integral to maintaining patient safety and achieving optimal patient outcomes in nursing, including in mental healthcare settings, but there are potential discrepancies between its principles and their implementation in practice. There are numerous barriers to safe medicines management in mental health services and it is not always perceived as a core element of mental health nurses’ identity. However, mental health nurses have critical roles in medicines management, including supporting informed choice, reporting medication errors, promoting adherence to medicines, and deprescribing. This article offers an overview of some of the principles of medicines management particularly relevant in mental health nursing and argues that improved postgraduate training in medicines management for mental health nurses is needed.