Q: How should I address the Dutch royals?
A: The Queen should be addresses as "Your Majesty". Other members of the royal family should be addressed as "Your Royal Highness"
Q: Which Kings/Queens have abdicated in The Netherlands?
A: King Willem I abdicated on 7 October 1840 and was known from there on as Count of Nassau. Queen Wilhelmina abdicated on 4 September 1948 . Queen Juliana abdicated on 30 April 1980.