Delivering information to the patient is one of the most significant of a physician’s commitments. The physician should inform the patient about his or her diagnosis about the disease, nature and scope of medical practices, consequences and possible risks and something like these. The physician should also help the patient access correct and sufficient information in this regard so that s/he can make decision knowingly about what will be done to his/her body. Failure to accomplish this commitment can be considered as a professional failure and finally, leads to his/her responsibility. The author of the present article tries to study different aspects of a physician’s commitment to inform patients with a comparative view to legal systems of countries other than Iran.