A patient approaching a doctor expects medical treatment with all the knowledge and skill that the doctor possesses to bring relief to his medical problem. The relationship takes the shape of a contract retaining the essential elements of tort. A doctor owes certain duties to his patient and a breach of any of these duties gives a cause of action for negligence against the doctor. The doctor has a duty to obtain prior informed consent from the patient before carrying out diagnostic tests and therapeutic management. The services of the doctors are covered under the provisions of the Consumer Protection Act, 1986 and a patient can seek redressal of grievances from the Consumer Courts. Case laws are an important source of law in adjudicating various issues of negligence arising out of medical treatment.

There exists a duty to obtain prior consent (with respect to living patients) for the purpose of diagnosis, treatment, organ transplant, research purposes, disclosure of medical records, and teaching and medico-legal purposes. With respect to the dead in regard to pathological post mortem, medico-legal post mortem, organ transplant (for legal heirs), and for disclosure of medical record, it is important that informed consent of the patient is obtained. Consent can be given in the following ways:

1. Express Consent: It may be oral or in writing. Though both these categories of consents are of equal value, written consent can be considered as superior because of its evidential value.
2. Implied Consent: Implied consent may be implied by patient's conduct.
3. Tacit Consent: Tacit consent means implied consent understood without being stated.
4. Surrogate consent: This consent is given by family members. Generally, courts have held that consent of family members with the written approval of 2 physicians sufficiently protects a patient's interest.
5. Advance consent, proxy consent, and presumed consent are also used.