Although there is increasing recognition of the existence of 'difficult' patients who present particular challenges to mental health nurses, no research has been conducted into their perceptions of services and their experiences of care. This study identifies mental health service users who are defined by nurses as 'difficult' and explores their perceptions of their care experience. The results support earlier studies which suggested that 'difficult' patients challenge nurses' competence and control: despite their different roles both nurses and 'difficult' patients were aware of the struggle to gain or retain a notion of control. Respondents were able to identify the qualities of nurses and nursing interventions which had a positive effect on their care experience. Where nurses were perceived to demonstrate respect, time, skilled care and a willingness to give patients some control and choice in their own care, feelings of anger were reduced. These findings are discussed within the conceptual framework of 'power over' and 'power to' and implications for practice and research are considered.