Managing behaviour is a complex component of the teaching process and one that teachers consistently identify as an area of great concern. This study aimed to examine teachers' perceptions regarding their competence for managing the challenging behaviour of young children and to identify the factors that affect these beliefs. A total of 204 preschool teachers working in Kindergarten Rijeka, Croatia participated. Teachers completed an exploratory survey of self-perceptions of competence in managing the challenging behaviours encountered in their classrooms. Factor analysis revealed a one-factor structure for self-perceived competence, and all scales showed good psychometric properties. Preschool teachers' assessment of their own competence in managing challenging behaviour was explained by the level of support they received from other professionals when faced with children's challenging behaviour and prior coursework in classroom management. Participants with higher levels of professional support and more coursework in classroom management estimated themselves to be more competent in managing challenging behaviour. The results suggest that Croatian preschool teachers need training in classroom management and greater access to professional support personnel when working with students with challenging behaviours.