The primary health care team (PHCT) has a critical role to play in the care of people with mental health problems. However, little attention has been paid to the mental health training and preparation required by primary health care nurses. This paper reports on a training needs assessment undertaken in one London health authority area. The findings indicate that primary health care nurses are undertaking a wide range and increasing volume of mental health work with little preparation and training. Specific training needs include time and space to identify training gaps; basic training in mental health, safe working practices and management of role boundaries; and multidisciplinary training. In addition, NHS trusts, primary care groups and health authorities need to clarify which aspects of nurses' mental health workloads are appropriate to their role and develop policies, procedures and training to support them in undertaking that role.