1. Introduction : general themes, reform, chapter overview 2. Mental state defences : insanity and automatism 3. Disease of the mind : individual justice and societal protection 4. Drug-use and the defence of insanity 5. Volitional insanity : involuntariness, injustice, and cognitive impairment 6. Involuntary conduct : defence of impaired consciousness 7. Conclusion : reform proposals, looking forward.