Article 7 of Mexico’s Federal Labor Law begins: “En toda empresa o establecimiento, el patrón deberá emplear un noventa por ciento de trabajadores mexicanos, por lo menos” (In every company or establishment, the employer must employ at least ninety percent Mexican workers). Technicians and professionals must also be Mexican.
When no Mexican worker has a specialty, foreigners may be hired for a time, up to ten percent of that specialty. They and the employer must then train Mexican workers in it. Company doctors must be Mexican. The rule does not apply to directors, administrators and general managers.