SINGAPORE - He deals with people every day, training others in interpersonal skills.
But twice every week, Mr Ong, 67, trades his suit for casual wear and heads to his marina at West Coast where he fires up his 9.4m cabin cruiser for a day - and night - of fun.
He pilots his boat, Nimbus, to a deserted island hideout, where a select few go to escape the crowd and the bustle of city life. Mr Ong said he bought his boat about 30 years ago and it is worth about $500,000 now. He does not have to travel far on it. The island is not some fancy resort in Malaysia or Indonesia.
It is at the bay of Seringat-Kias, at Lazarus Island in Singapore, a mere 3km south of Sentosa.
The island is the secret playground for those who can afford to own and maintain a pleasure craft.
"It's a beautiful place to be," said Mr Ong, the chief executive officer of a consultancy firm.
To others, it is a place to go wild at night.
Said Mr Edwin Tan, 49, who owns the 11.4m cabin cruiser Tequila Sunrise 8: "This is a party island. Come nightfall, you'll see some pretty wild parties here."
Mr Tan runs a local commercial diving company. He bought his boat last year for $500,000.
Lazarus Island's pristine beach stretches about 800m and the quiet coastline is home to anemones, sea stars and other creatures.
Stingrays and coastal dolphins are occasional visitors.
As the sun sets, white-headed sea eagles can be seen circling the rising thermals from the island's forested centre.
Said Mr Ong, who started visiting the island 10 years ago: "If you are a boating person, you would know about this place. Otherwise, very few Singaporeans know Lazarus exists."
Lazarus, which is part of the Southern Islands, is too expensive and inconvenient for non-boat owners to reach. (See other story on right.)
That makes it an island of choice for boat owners seeking solitude out of more than 60 islands in Singapore. When The New Paper visited the island on Sunday morning, more than 10 boats and yachts dotted the calm waters at Seringat-Kias.
The beachgoers were swimming, kayaking or just lazing on the bow of their yachts in bikinis and board shorts.