This chapter seeks systematically to examine the notion of power in nursing and how it can impact upon the relationship between nurse, informal carer and patient. The relationship between the patient, the informal carer and the nurse has come under greater scrutiny as government policies drive a strong agenda of improved consultation and greater consumer involvement in healthcare. This philosophical shift requires nurses to reappraise the roles normally adopted within the care process, as well as to acknowledge that power relationships will need to change to accommodate more equal, patient-focused care interventions. The tension between the nurse’s duty of care and the patient’s right to self-determination within the care partnership is explored in depth.