"I want to do it myself, to be responsible for it myself," the former business manager, 78, told AFP he was still perky and alert, loved tending his flower garden, listening to opera and reading.
But the day he loses his independence and the ability to participate in village life will be the day to consider "going away."
"I shall be the director of my own final scene," he said.
Hillebrand is one of a growing number of aging Dutch people who prefer to make their own decisions about when and where to die -- and in a dignified way.
"Senior citizens today like to decide things for themselves, more than previous generations," said Ton Vink of De Einder (The Ender in Dutch), an organisation dedicated to "informing" people who want to end their own lives.
More and more Dutch voices are being raised in support of a right to claim assistance to die with dignity after "an accomplished life" and not just when the requirements by law for euthanasia are fulfilled.
A citizens' initiative called "An Accomplished Life" which supports the idea, has already gathered more than 117,000 signatures, more than the 40,000 required for a debate in the Dutch parliament, which was held in early March.
Even with the country's liberal laws on euthanasia, a doctor still has the final say whether the criteria have been fulfilled for assisted suicide, namely unbearable and prolonged suffering caused by incurable disease.
But Hillebrand said: "I have no desire to go and fight" against a "wicked" disease, to be forced to live "a life in prison like a larva," in a hospital or an old-age home.
The septuagenarian bought his 50 "suicide pills" illegally in the Netherlands, politely declining to say how and where -- except that it was "very easy."
When his hour arrives, whether in five, 10 or 20 years, Hillebrand, who wants to donate his body to science, has left nothing to chance: the names to go on envelopes to tell people of his demise have already been written.
But unlike Hillebrand, many pensioners are often unable to secure so-called "suicide drugs" and then choose a more radical option.
"Sometimes people who want to die have to end their lives in a cruel way," by jumping off a bridge or throwing themselves underneath a train or setting themselves on fire, said Walburg de Jong, spokesman for Right-to-Die NL (NVVE).
A book titled "Solution" written by Dutch psychiatrist Bowdewijn Chabot and published in February 2010, explained how people could end their lives by using the necessary drugs like barbiturates, anti-depressants and opiates, as well as dosages.
Some 11,000 copies have been sold since.
AFP/ Nicolas Delaunay / Expatica
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