An unassuming 53-year-old who likes playing the piano in his spare time, he is responsible for the security of $4 trillion (£3.2tn) of bank deposits around the world.
Mr Fernandez is the founder and boss of a company that is as little known as he is - Avaloq. It is one of the world's largest providers of banking software.
To help make its software as secure as possible, the company has a novel approach - it pays technology firms in Israel to attack it.
Bulletproof
Read More: High security: The man who protects our bank accounts - BBC News
Mr Fernandez is the founder and boss of a company that is as little known as he is - Avaloq. It is one of the world's largest providers of banking software.
used by more than 450 banks around the world, including the UK's Barclays, HSBC, and Royal Bank of Scotland, plus Deutsche Bank, Societe Generale, UBS and Nomura
To help make its software as secure as possible, the company has a novel approach - it pays technology firms in Israel to attack it.
Bulletproof
"The Israelis are very, very good, they [the young tech workers] are coming out of active military service, and they are brilliant.
We regularly appoint them to attack our systems in a controlled way, and then with their help we try to make our systems bulletproof.
We do our homework, security is a constant thing... we get thousands of attacks per year but so far, touch wood, we have never had an intrusion into our systems." - Mr Fernandez
We regularly appoint them to attack our systems in a controlled way, and then with their help we try to make our systems bulletproof.
We do our homework, security is a constant thing... we get thousands of attacks per year but so far, touch wood, we have never had an intrusion into our systems." - Mr Fernandez
Read More: High security: The man who protects our bank accounts - BBC News