Consent to a treatment can be given either orally or in writing, as is common where doctors provide consent forms for patients to sign. There are some situations where consent of a patient is implied, as where the patient exhibits conduct indicating a willingness to undergo the treatment, or in the case of an unconscious patient who is unable to consent, and there is no family member available to give consent on his or her behalf (and no living will which directs otherwise).

If the patient is a child it is usually necessary for a parent or guardian to consent to any treatment, unless treatment is required in an emergency situation and the parent or guardian is unavailable to give consent. Exceptions may apply to situations where a minor seeks treatment for a sexually transmitted disease, or for alcohol or drug problems.

The damages a patient may recover in this kind of medical liability action are different from the damages that might be obtained in a medical malpractice negligence action. Because the liability relates to the lack of consent to a procedure, a patient may be able to recover damages even if the medical procedure was successful, whereas in a negligence case, the plaintiff is required to prove damages.