For the man friends call Alexander or Alex is on the verge of fulfilling his destiny, with his inauguration as King of the Netherlands.
On 30 April, three days after his 46th birthday, Willem-Alexander will become the first male to ascend the throne since 1890.
Life is about to change for the Crown Prince and Princess
Standing in Amsterdam's gothic Nieuwe Kerk or New Church, he will be sworn in as head of state draped in the ermine mantle previously worn by his mother Queen Beatrix and their ancestors before that for the last two centuries.
This will mean changes to the lives of the new King and Queen. The most significant is that the couple and their three girls Amalia, nine, Alexia, seven, and five-year-old Ariane will, in the fullness of time, move to Huis ten Bosch Palace a few miles away in The Hague.
Beatrix, who is abdicating in her son's favour, will move into Drakensteyn Castle in Lage Vuursche.
Queen's Day, the official celebration of her birthday, will become King's Day. From now on to honour her heir the national party at which revellers wear orange, the national colour, will be held on 27 April.
In anticipation of a heavier workload, the Prince has already given up some of his outside interests. He has resigned his membership of the International Olympic Committee and chairmanship of a United Nations board on water and sanitation.
Up until now they have only had a supporting role in the monarchy
The royal seemed relaxed and confident, buoyant even, about his new responsibilities during a recent TV interview watched by 4.6 million viewers, which is almost one in four of his people.
Willem-Alexander promised his countrymen that he would be "be a 21st-century king, someone who inspires and accurately represents Dutch society."
With regard to the advice his mother had given him, the Prince said: "The Queen urged me to stay myself, to hold my own course and try not to go along with (every new wind) because that will break you".
Despite the serious topics covered in the interview, he even found time for a joke. Asked if he would reign as Willem IV, the royal said he would be known as King Willem-Alexander.
Referring to the way cows are named, he quipped dryly: "Willem 4 stands next to Bertha 38 in the meadow".
Villa Eikenhorst in Wassenhaar just down the road from The Hague
There is only one shadow as the Dutch monarchy celebrates an exciting new beginning. For over a year the family has been watching over Prince Johan Friso, his younger brother, who has been in a coma since a skiing accident.
Describing it as "a great tragedy", Willem-Alexander said: "For my part, all I can do is support (my mother and his wife Mabel) – and make sure I do my best on 30 April."