Operative vaginal delivery and emergency caesarean are common obstetric interventions. To give valid consent to these procedures, a person must have the mental capacity to make the decision, be provided with relevant information and be free from coercion. Obtaining proper consent during labour can be problematic. Emergencies can arise requiring urgent intervention, with little time for discussion. The woman may be in pain, exhausted, or afraid. These factors can temporarily impair a woman's capacity to give consent, and exhaustion/fear may be unavoidable even with good pain relief. Family members are often present and untangling their wishes from those of the woman herself can be difficult. It can sometimes be impossible to obtain truly valid consent during labour; in these circumstances it might be better described as ‘assent’ to a recommended course of action. Clinicians are responsible for providing information. The patient's right to self-determination is enshrined in both professional guidance and law. Information must be comprehensible, with the onus on the clinician to ensure their patient has sufficient knowledge to make the best possible decision for herself. The Royal College of Obstetricians and Gynaecologists has published guidance for clinicians on taking consent both for caesarean section and operative vaginal delivery. These provide comprehensive information and serve as a useful guide to discussions between a woman and her clinician. However, although obtaining written consent for urgent operative intervention is considered good practice, it is not a legal requirement. In an attempt to make things easier, many hospitals provide preprinted consent forms containing information replicated from professional guidance, but asking the woman to read and sign the form does not of itself constitute consent. Without appropriate dialogue, the consent form is meaningless, and may even be a distraction. Furthermore, requesting a signature in some circumstances could be perceived as defensive practice, serving to protect the hospital if anything goes wrong. This risks erosion of trust between the woman and her clinician, given that in many situations women have no realistic alternative than to acquiesce to their doctor's recommendation. Even worse, it can delay urgently required intervention. A signature on a preprinted form is not by itself proof of consent. Taking proper consent from women during labour requires skill and judgement and cannot be standardised. Where there is insufficient time to provide detailed information to women, or for them to read and sign preprinted consent forms, it is essential to record the dialogue and decision-making process in the written record in as much detail as possible, either at the time, or very soon afterwards. Official guidelines are a tool to inform the consent process, and cannot replace proper dialogue. In the USA it is common practice to meet with women during pregnancy to discuss their delivery, and to take written consent for operative intervention before the onset of labour. Although this practice may appear defensive, it fits in with the model of informed consent that the UK legal system also now demands, giving women greater autonomy over their birth choices. None declared. Completed disclosure of interests form available to view online as supporting information. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.