The surety acts as a guarantee deposited in favor of the fulfillment of a contractual obligation. In general, its contracting covers our contractual obligations towards a third party.
In some cases it will be imposed on us by imperative of the contract. Acting as suppliers of the public administration, we will be required to contract it, to cover our obligations for a part of the amount of the contract.
It can also be contracted to insure third-party obligations.