The obligation to guarantee safety is considered one of the most important topics that have occupied the attention of modern jurisprudence and judiciary, as it has become applied in most fields, such as consumer protection and the responsibility of producers, sellers and carriers, as its features and rules have been precisely defined. As this obligation has tried to invade the medical field, we have therefore researched, to what extent is this obligation applied in the medical field? Given that this field has its own considerations because it contains the element of probability that controls the medical work that the doctor cannot guarantee any result, the necessity of applying this obligation in the medical field is logical due to the importance and sanctity of its subject, which is the safety of the patient's body, which is the reason for our choice to study this topic to try to find a kind of reconciliation between the doctor's freedom to choose a specific method of treatment and the patient's right to his safety and protection from doctors' errors and the resulting damages. It should also be noted that the roots of the codification of the idea of the obligation to guarantee safety legally go back to the French judiciary when I see the application of justice standards in contracts.