The conference's organisers said: "We want to debunk the myth that rape in war is somehow inevitable or a lesser crime."
In a speech made overnight, Mrs Collins said sexual violence was an abhorrent crime that perpetuated conflict and instability. She was heartened by the high-level support of 70 Government ministers in finding practical ways to reduce danger to women in war zones.
Mrs Collins highlighted New Zealand's progressive approach to women in conflict and peacekeeping.
She told the audience that women had been able to participate in all areas of the Defence Force since 2000.
"All roles, including combat, are open to women - however, we still have a long way to go to ensure equal participation at all levels of our Forces," she said.
She spoke of her visit to Bamiyan Province in Afghanistan, where New Zealand policewomen were part of the troops.
In Wellington, the British High Commission hosted an event outside Te Papa Museum - including a flashmob of dancers - to coincide with the summit.
High Commissioner Vicki Treadell said rape in conflict areas should be recognised as a war crime, similar to genocide or torture. "Rape has been used as a weapon of war repeatedly in our lifetimes on every continent and in every major conflict. It has nothing to do with sex and everything to do with power and the desire to conquer and humiliate."
Women in conflict zones
Global Summit to End Sexual Violence in Conflict:
•Largest ever conference on sexual violence against women in conflict areas.
•Attended by 70 government ministers, including Justice Minister Judith Collins.
•Aims to create new international standards for investigating and prosecuting rape in conflict zones.
•Outlines practical steps for reducing dangers to women in war, including greater education of soldiers and peacekeepers.