Prime Minister Harper meets with the Secretary-General of NATO today, with Iraq and rising tensions with Russia likely to be the main topics of discussion.
It's Jens Stoltenberg first visit to Canada and it comes the same week Harper is expected to ask the House of Commons to extend and expand Canada's military involvement in Iraq.
NATO has had no formal role in fighting the Islamic State in Iraq and the Levant, but a source close to today's meeting says the two men will discuss the ISIL threat.
Russian President Vladmir Putin's recent moves, including mobilizing 45-thousand troops for military exercises last week, have been the alliance's major preoccupation.
NATO's supreme allied commander has said the west should consider sending defensive weapons to Ukraine.
Defence Minister Jason Kenney has dropped broad hints that Canada could soon provide Ukraine with more military assistance.