Many end up working in an English-speaking field
Dutch graduates don't mind having classes in English

Over the past few years, the Dutch Parliament has been concerned about the number of English-taught degrees in the Netherlands. Many MPs question whether those programmes need to be taught in English in the first place, wondering if graduates need the English language later in life. The Ministry of Education has commissioned ResearchNed to survey 9,000 graduates to find the answer to that question.
Here's what they found: after an English-taught degree, Dutch graduates are more likely to find a job that only requires them to speak English. Only 2.6 percent of graduates with English-taught degrees end up in a completely Dutch-speaking workplace. The opposite happens slightly more often: five percent of graduates with Dutch-taught degrees end up working in a completely English-speaking environment.
No problem
Either way, Dutch graduates do not seem to have a problem with the language of instruction. More than 90 percent of those surveyed say that the language of instruction used at university matches the language they use at work.
Dutch remains an important language in the labour market, as 34 percent of Dutch graduates never or seldom use English at their jobs. Just over 50 percent of respondents need to use English in addition to Dutch regularly. Only 14 percent say the main language used in their workplace is English.
No internationals
International graduates were not included in this survey. ResearchNed says an additional study should be conducted to find out how many of them end up in a Dutch-speaking workplace and, if so, how that goes.