Under EU law a citizen of an EU country can work in any other EU country without the need for a work permit. It's probably true to say that a non-Dutch speaker has got little or no chance or ever getting an appointment at KLM. A fluent English speaking Dutchman has no legal impediment to prevent them working for a UK/Eire based airline. Some may no agree with employing people from outside the home country but unfortunatley there is nothing legally to prevent it. In fact, if a company discriminated against someone from another country who was qualified for the position they could find themselfs in court.