Ask a room of aesthetic practitioners what informed consent requires and most will describe a form: risks listed, boxes ticked, signature at the bottom. That answer was arguably adequate in 2014. It has been wrong in law for over a decade, and the gap between what clinics do and what courts expect is where claims are won and lost.
This article sets out how the law of consent moved between 1957 and 2023, and what that movement means, concretely, treatment by treatment, for an aesthetics consultation in 2026.
Before 2015: the doctor decided what you needed to know
For nearly sixty years, consent was governed by the same test as clinical negligence generally: the Bolam test, from Bolam v Friern Hospital Management Committee [1957] 1 WLR 582. A doctor was not negligent if they acted in accordance with a practice accepted as proper by a responsible body of medical opinion. Applied to consent, that meant the profession set the standard for disclosure. If a responsible body of practitioners would not have warned about a given risk, failing to warn was defensible, whatever the patient might have wanted to know.
The test was doctor-centred by design. It survived challenge in Sidaway v Board of Governors of the Bethlem Royal Hospital [1985] AC 871, though with growing judicial unease. That unease finally broke in 2015.
Montgomery: the facts and the new test
Nadine Montgomery was a diabetic woman of small stature, pregnant with a large baby. Diabetic mothers carry a roughly 9–10% risk of shoulder dystocia in vaginal delivery. Her obstetrician did not discuss that risk, nor the alternative of elective caesarean section, on the stated view that if told, most such women would choose a caesarean, which the obstetrician did not consider to be in their interest. Shoulder dystocia occurred. Her son was deprived of oxygen during delivery and was born with cerebral palsy.
In Montgomery v Lanarkshire Health Board [2015] UKSC 11, the Supreme Court found for Mrs Montgomery and, in doing so, removed consent from Bolam's reach. The duty is now expressed as follows: a doctor must take reasonable care to ensure the patient is aware of any material risks involved in a recommended treatment, and of any reasonable alternative or variant treatments.
A risk is material if a reasonable person in the patient's position would be likely to attach significance to it, or if the doctor is or should reasonably be aware that this particular patient would be likely to attach significance to it.
Two things in that sentence deserve careful reading. First, the test has two limbs: the objective reasonable person in the patient's position, and the subjective particular patient in front of you. Either is enough. Second, the court was explicit that materiality cannot be reduced to percentages. A statistically small risk can be material because of the severity of its consequences, because of its importance to this patient's life and priorities, or both. A 0.03% risk of a catastrophic outcome may demand a fuller conversation than a 10% risk of a trivial one.
The court also made a point that aesthetics should hear clearly: the duty is not discharged by "bombarding the patient with technical information" or by "routinely demanding a signature on a consent form". Consent is a dialogue, and the form is merely evidence that the dialogue happened.
Duce: the two-stage clarification
In Duce v Worcestershire Acute Hospitals NHS Trust [2018] EWCA Civ 1307, the Court of Appeal tidied Montgomery into a two-stage structure. Stage one: what risks associated with the procedure were, or should have been, known to the practitioner? That is a matter of professional knowledge and expertise, assessed by reference to the profession. Stage two: was the patient told about those risks, and is each one material? That is for the court, applying Montgomery, not for a responsible body of practitioners to settle among themselves.
The practical consequence: you cannot outsource materiality to your peers. "Nobody in my training cohort mentions that complication" answers stage one at best. It says nothing about stage two.
McCulloch: alternatives get their own test, and their own paper trail
Montgomery's second limb, reasonable alternative treatments, waited eight years for clarification. In McCulloch v Forth Valley Health Board [2023] UKSC 26, the Supreme Court held that deciding which alternatives are reasonable is an exercise of professional judgement, assessed by the professional-practice test: if a responsible body of practitioners would not regard an option as a reasonable alternative for this patient, you need not offer it.
But the corollary carries the practical weight. Once an option is a reasonable alternative, you must disclose it, all of them, not just your preferred one, and you should be able to show why excluded options were excluded. For clinics, that translates into a documentation habit most consent forms never contemplated: recording not only what you offered, but what you considered and ruled out, and your reasoning.
What this means treatment by treatment
Aesthetics is elective. No patient needs a dermal filler, which means the courts and regulators expect the consent conversation to be more careful, not less. Applying the case law to the everyday treatment menu:
Dermal fillers: vascular occlusion is a material-risk conversation
Vascular occlusion is rare. It is also potentially catastrophic, skin necrosis, and in the worst cases visual loss. Under Montgomery, its rarity does not remove it from the conversation; its severity puts it squarely in. A reasonable person considering a cosmetic injection would be likely to attach significance to a risk, however small, of losing tissue or sight. A consent process that buries vascular occlusion in a list of twenty bullet points, or omits it, is answering the pre-2015 question. The conversation should cover what the complication is, the warning signs, what the emergency response involves, including hyaluronidase, and the practitioner's preparedness for it.
Botulinum toxin: ptosis and the temporary-but-real problem
Ptosis after toxin is usually temporary and rarely dangerous. But for the particular patient in front of you, someone with a client-facing role, a wedding in six weeks, a history of anxiety about their appearance, a drooping eyelid for several weeks may be exactly the kind of risk they would attach significance to. Montgomery's second limb does the work here: what you know, or should know, about this patient shapes what you must discuss. That is why a consent process needs a mechanism for capturing patient-specific concerns, not just a generic risk list.
Hyaluronidase: the rescue drug needs its own consent
Hyaluronidase is the emergency answer to filler complications and an elective tool for dissolving unwanted filler. It carries its own material risks, including anaphylaxis. A clinic that consents carefully for filler and then administers hyaluronidase on a verbal "shall we just dissolve it?" has recreated the original problem one step downstream. Elective dissolving deserves its own documented dialogue; emergency use deserves a documented protocol.
The alternative that is always reasonable: no treatment
In elective aesthetics, doing nothing is a reasonable alternative to every procedure, every time. McCulloch makes discussing it a legal expectation, not a courtesy. So is the less invasive option: skin treatment before filler, filler before surgery, review before more. A record that shows the patient was offered nothing-at-all and something-less, and chose to proceed anyway, is one of the strongest documents a defence can hold.
Seven features of a Montgomery-compliant consent process
Case law rarely tells you what good looks like operationally. Ten years of judgments, GMC guidance and claims experience do. A consent process that would withstand scrutiny has seven features:
- Dialogue, not paperwork. The consultation is a documented two-way conversation. The form evidences the dialogue; it does not replace it.
- Tailoring to the particular patient. The record captures this patient's circumstances, occupation, concerns and priorities, and shows the risk discussion responding to them.
- Alternatives, including no treatment. Every reasonable option is disclosed; excluded options are noted with reasons, per McCulloch.
- A genuine cooling-off period. The GMC's 2016 guidance on cosmetic interventions expects patients to have time to reflect between consultation and treatment, and prohibits same-day consent-and-inject for new procedures as routine practice. The gap should be real, and recorded.
- Contemporaneous records. Notes made at the time, capturing what was discussed, what was asked, and what the patient decided. A record reconstructed after a complaint is worth little; one made in clinic is the best witness you will ever call.
- Review and re-consent. Consent is refreshed when the treatment plan changes, when material time has passed, and when new risks emerge in the literature. A signature from 2024 does not cover a different product in 2026.
- A trained team. Everyone who touches the consent pathway, reception booking the cooling-off gap, the practitioner leading the dialogue, the colleague witnessing, understands why each step exists. Consent fails at the weakest point in the pathway, not the strongest.
Most clinics have two or three of the seven. Very few have all of them, in writing, consistently applied. The difference matters only on the day it matters, and by then it cannot be fixed retrospectively.
Where to start
The honest first step is not a new form. It is finding out whether your current process, forms, consultation notes, cooling-off practice, record-keeping, would survive the two-stage Duce analysis in front of a claimant solicitor. That is precisely what a structured audit does: it scores your existing consent pathway against Montgomery, McCulloch and regulator guidance, and shows you where the gaps are before someone else finds them.
Get your consent process assessed →
Related reading: the England licensing scheme timeline · why claims are lost on paperwork, not outcomes · done-for-you consent systems