| ElBaradei steps down as head of the IAEA, the UN nuclear agency, in November [GALLO/GETTY]
From his comfortable office in the sprawling UN complex in Vienna, the Austrian capital, Mohammed ElBaradei runs the world's nuclear watchdog.
The International Atomic Energy Agency (IAEA) is never far from the headlines, whether it's dealing with North Korea's not so secret tests, Iran's ongoing nuclear programme or the Americans and the Russians pledging to cut their nuclear arms weapons.
After 12 years in charge, the Egyptian director-general is walking away.
He will step down in November leaving someone else to fight the battles.
His office is large but uncluttered. On his desk are a number of books, some press cuttings but most obviously, pictures of his family he proudly describes as "citizens of the world".
He arrives early. We have an hour, but there's lots to talk about, most obviously what the events in Iran over the past week mean to the country's nuclear ambitions.
He believes that the government in Tehran wants the technology for a nuclear weapon but he says that does not mean they are going to build one.
"They are six or seven years away from that, so we're not going to wake up and find a nuclear armed Iran."
He knows the Israelis are running out of patience with talks about talks but animatedly warns against military action.
"The Israelis might decide to bomb the facilities in Iran, this would be the wrong thing to do.
"President Perez has himself said you can't bomb knowledge. All you do would be to delay Iran's technology programme a couple of years.
"But I can assure you that if they have no intention to develop nuclear weapons, they will go into a crash course to develop nuclear weapons. They bombed Iraq in the 1980s and Saddam launched a clandestine nuclear operation. Military action is not the answer."
Iraq is the one thing that Dr ElBaradei struggles with each morning when he looks in the mirror - the war and all its consequences.
But the thing keeping him awake at night is nuclear terrorism.
He fears an "extremist" group getting hold of some radioactive material that could be used in a dirty bomb.
"We have to make sure all radioactive material is in good hands, applying the gold standard to the physical protection of these materials because you have these extremist groups don't have deterrence as part of their ideologies.
"If they have it, they'll use it. It would be easy to get to radioactive sources.
"We have to have full funding to do a credible job in stopping this. It is the top priority in the world. We need to be a watchdog with bite."
For many, the biggest nuclear threat remains North Korea, which has carried out two recent tests.
It was a problem when ElBaradei took charge of the IAEA and now 12 years later, it remains unresolved.
"We have learned a lot of lessons from dealing with North Korea. Every time talks broke down with North Korea, there was a problem. So the lesson must be to keep talking and keep them engaged," he said.