When a patient presents to hospital after a suicide attempt and appears to refuse treatment, clinicians should first assess if he or she should be treated under mental health legislation, regardless of competence to refuse treatment. When it is not possible or is inappropriate to treat under mental health legislation, the person's competence to refuse treatment should be assessed. If the patient is definitely competent, his or her decision to refuse treatment should probably be honoured. If an incompetent patient carries a document refusing treatment, clinicians must determine the validity of that document as an advance care directive - including whether or not the patient was competent at the time it was written. The law around the right to refuse treatment after a suicide attempt remains unclear and, if uncertain of what to do, clinicians should provide urgently required life-saving treatment and simultaneously seek an urgent court order to clarify how they should proceed. In all but extraordinary circumstances, a patient who refuses treatment after a suicide attempt can and should be given life-saving treatment, under either mental health legislation or the common law concept of necessity.