This exploratory descriptive study used focus groups to investigate experienced mental health nurses' perceptions of expertise in relation to their practice. Two focus group discussions were conducted, one comprising four nurses working in inpatient care and the other with five nurses working in community care. The nurse-patient relationship was the central theme for both groups. Three sub-themes were identified and are discussed. They are involvement, individualizing care, and minimising visibility. The significance of these themes for the articulation of mental health nursing practice is discussed.