Mental health nurses are faced with an increasing number of aggressive incidents during their daily practice. The coercive intervention of seclusion is often used to manage patient aggression in the Netherlands. However, GGZ Nederland, the Dutch association of service providers for mental health and addition care, has initiated a project to decrease the number of seclusions in clinical psychiatry. A first step in this project is to gain insight into the current situation: the perceived prevalence of patient aggression, the attitudes of mental health nurses towards patient aggression and those socio-demographic and psychosocial factors that contribute to the use of coercive interventions. A survey was undertaken among 113 nurses from six closed and semi-closed wards. In this survey, two questionnaires were used: (1) the Attitude Toward Aggression Scale; and (2) the Perceptions of the Prevalence of Aggression Scale. Variables derived from the Theory of Planned Behaviour were also measured. Nurses reported being regularly confronted with aggression in general and mostly with non-threatening verbal aggression. They perceived patient aggression as being destructive or offensive and not serving a protective or communicative function. The nurses generally perceived themselves as having control over patient behaviour (i.e. considerable self-efficacy) and reported considerable social support from colleagues. Although the nurses in this study were frequently confronted with aggression, they did not experience the aggression as a major problem. © 2008 The Authors.