He does have a weakness for cigars, but he is physically small, immaculately groomed, and speaks softly with a Cambridge University correctness.
But no-one who has sat across a deal table from him or witnessed his ability to make swingeing job cuts would see Sir John as anything other than a tough campaigner.
The 50-year-old BP boss is loved in the financial community for the remarkable rehabilitation of the company's share and trading performances in recent years. But he is also respected across the Atlantic where BP is liked and its shares busily traded on Wall Street.
He has considerable experience working all over North America and is chairman of the advisory board at Stanford business school, where he completed his academic training.
Sir John actually began his education at an American school, but that was in Iran where his father was posted by his employer, BP.
Although Browne junior comes across as the perfect English gentleman, he was born in Hamburg and his mother is Rumanian.
With his father now dead, Sir John lives as a bachelor with his mother, Paula, in his Belgravia home. She can be seen at his side at BP social functions and at the opera when Sir John indulges one of his few passions.
But the real family in Sir John's life is BP: He is renowned for working enormous numbers of hours. His sense of commitment goes back to his days at King's School in Ely and then St John's College, Cambridge.
He came out with a first in physics and went on to Stanford, falling in love with the US. He joined BP and had spells in Alaska, New York and San Francisco.
In 1984, Sir John was whisked back to head office by chairman Bob Horton to become chief treasurer before being put in charge of exploration.
In 1991 he joined the board, and four years later he became chief executive working alongside Lord Simon, the BP chairman who has moved into government.
Where Lord Simon was sociable and media-friendly, Sir John has remained aloof and intensely private.Reuse content