Prime Minister Stephen Harper acknowledges that the G20 summit was an inconvenience to Torontonians, but says meetings like the one that took place in Canada's largest city this past weekend are the only way world issues move forward.

"Somebody told me when I first became Prime Minister - somebody who knew a little bit about the job - told me that even though the government of Canada is large and complex and there's hundreds and even thousands of people working on any problem, very little actually happens in the end unless the Prime Minister makes sure it happens," Mr. Harper said Monday in an interview with CTV Canada AM.

Public servants and political staff have been working with their G20 counterparts regularly and intensely over the last six months, he said.

But "the fact that, if things are not resolved it will end up on the leader's plate, potentially in a very tense dinner conversation, is the thing that drives these things to a conclusion. So, in the end, the leaders' meeting is what makes everything else work."

Even in an age when teleconferences are so easy to organize, said Mr. Harper, there is nothing that can replace getting together with somebody face to face, shaking their hand, talking to them, and understanding their own pressures and concerns.

Despite the lock-down of the Canada's largest city, the wanton destruction by vandals and the hundreds of arrests, Mr. Harper said he believes that "99.9 per cent of Torontonians were very pleased and honoured to have these leaders here and were very hospitable."

World leaders have come to expect the sort of violence that ensued, he said.

"We attend summits all of the time and we know the unfortunate reality is that these summits attract a certain thuggish criminal," he said. "We've seen it in other cities, we are going to see it again in the future."

Mr. Harper sounded a little tired during the interview - it had been a long week. But he said he actually felt pretty good.

The most important personal lesson that a Prime Minister must learn is how to manage the stress, he said. And that means managing sleep.

"There's always a temptation to cut into it, to say, you know, we can sleep a couple hours less in a night and make it up later," said Mr. Harper. "My experience is that's a mistake. You've got to sleep regularly, sleep well. I won't say that sometimes the stress doesn't trouble my sleep. But, by and large, I've been okay in that regard."

There is always extra pressure on the summit host, who must publicly explain the success or the failure of a conference such as this, he said. But Mr. Harper said he has been struck by the cohesion of the G20 leaders, both at this meeting and at previous events.

"I will never forget that meeting in Washington where we sat around the table (in 2008, as the economy was in a free fall) with countries that had been historic enemies, with leaders that I happen to know did not like each other very much in some cases," he said. "And yet everyone was saying what are we going to do together to stop this? And it's created a dynamic where I think we do understand we are all in the same boat, so my sense was that, while there is more pressure on the host ... all of the other leaders wanted this to be successful as much as I did."