In Spain, bosses need to sign contracts with workers. When hiring new workers, a work contract must be signed. When hiring a new worker, a copy of the worker's residence permit is required and the worker is required to sign a work contract. Most Chinese owners do not sign a work contract when they hire workers to work, and have their agents handle the contract registration with the Institute of Professional Registration (INEM). During an inspection by the Labor Department, the owner is required to show the contract signed with the worker. If the worker is still in the company, he can just sign a replacement. But if the worker has left, it will be very troublesome. When you hire a new worker, you must first get a copy of the residence permit from him. Later, if the residence permit is changed, you must get a copy of the new residence permit promptly so that it can be used in the future. When the agent issued the contract, the agent was asked to print out two copies of the contract and ask the workers to sign them. The company and the workers each kept one copy. On the one hand, it is used for inspections, or when conflicts arise between the company and workers.