In this study a path analytic approach was used to investigate predictors of the sense of competence in primary caregivers of demented persons. Data were gathered from 141 pairs of demented persons living in the community and their informal primary caregivers. Analysis of the information reported by the primary caregivers indicated that sense of competence and its component domains were affected above all by behavioural problems of the demented person and degree of neuroticism of the primary caregiver. No significant influence was found on the sense of competence of formal support of home helps and district nurses. The results suggested that the amount of support the demented person received from other social network members only had a limited influence on the domains of sense of competence.