Homeless people have complex health care needs, and they have difficulty accessing and utilising health services appropriately. These factors are associated with living in poverty, and in particular, residing in poor quality transient housing. Due to the complexity of their social disadvantage a flexible and timely response is required by emergency departments that extend beyond the traditional models of health care. The purpose of this integrated literature review was to identify the key risk factors that impact on the health service utilisation of people who experience homelessness.