Asymmetric information is when there is an imbalance in information between the buyer and the seller that can distort the choice. Clearly, the problem of asymmetry of information is generally present in the economy. Just availability of information determines the likelihood of making the right decision. As the economic relationship contains many information, it is to be expected that there is a greater or lesser asymmetry of available information. This asymmetry creates an imbalance in transactions, which can sometimes cause wrong transactions, some kind of market failure in the worst case. Examples of this problem are negative selection, moral hazard, and monopoly of knowledge. The information asymmetry is studied in the context of the main agent problem where they are the main cause of misinformation and are essential in each communication process. Information asymmetry is the opposite of perfect information, which is a key assumption in the neoclassical economy. Asymmetric information models assume that at least one party in the transaction has relevant information, while the other does not respond. Some asymmetric information models can also be used in situations where at least one party can carry out or effectively avenge violations of certain parts of the agreement, while the other can not.