Kafala is one of the most restrictive systems of access to the labour market for foreigners. The Kafala system is applicable in most Middle Eastern countries. It implies that a kafeel must sponsor you to enter the destination country and that you will be legally bound to this individual sponsor (kafeel) for the duration of the contract period. You cannot enter the country, transfer employment, nor leave the country without explicit written permission from the kafeel.
As such, if you are a migrant worker under the Kafala system, you are utterly dependent upon your kafeel for your travel, livelihood, and residency. Take this into consideration when you decide whether to apply for work overseas.