Is it permissible to work for an international shipping company that transports prohibited items – such as alcohol – from one country to another, knowing that the employee’s job is "managing customer issues and affairs"?

Working in institutions that transport documents and parcels is permissible, unless it specializes in transporting prohibited items, such as usurious documents or alcoholic beverages, in which case the work becomes forbidden. If the permissible mixes with the forbidden, the ruling is based on the predominant element, with the obligation to avoid forbidden acts. It is not permissible to work in transporting alcoholic beverages, films, or documents related to usury and insurance, because that falls under aiding in sin and aggression and brings about a curse, regardless of whether the recipient is a Muslim or a disbeliever. The fatwas of the Permanent Committee have stipulated the prohibition of working in the manufacturing or transporting of alcoholic beverages, and that earning from it is forbidden. It is advised to be keen on working in permissible matters and abandoning what Allah has forbidden, for whoever abandons something for the sake of Allah, Allah will compensate him with something better.