Rapid changes to the structure and delivery of mental health services in Australia, has increased the prevalence of mental health issues within the general health care system. In response to this, nurses now have more contact with people experiencing mental illness and mental health issues. Unfortunately these broad changes were not accompanied by education and training, and the available evidence suggests that nurses do not view caring for these people in a positive light, largely because they lack the necessary knowledge and skills to do so with confidence. This paper provides an overview of the prevalence of mental illness within the general health care system, with particular emphasis on the relationship between physical health and mental health. The need for nurses to respond to the complex needs of people experiencing mental illness is emphasised.