The vegetative state - a condition in which someone is awake but unaware with no evidence of a working mind - is both emotive and challenging. This condition and that of someone who gains partial recovery of mental and neurological functions - known as the minimally conscious state - have provoked intense debate and considerable interest amongst scientists, health care professionals, ethicists, philosophers and lawyers. This unique special issue unites many experts in the field to review and discuss the many advances made in our understanding of these conditions. The strength of this special issue lies in the wide range of topics discussed - from definitions and diagnostic criteria to hotly debated topics such as whether a person in the vegetative state is truly unaware. This edition will serve as both a useful reference to those caring for people in these conditions as well as to those investigating the physiological basis of human consciousness.