The head of Save The Children said some of things brought to light by the sex abuse scandal "disturb me" and praised reporters for uncovering abuses among international aid organisations.
Kevin Watkins said press coverage over the past month had been "uncomfortable" viewing but warned that it was not smart for charities to be "burying our heads in the sand".
Speaking in London on Friday at the launch of a report into the violence against children in war zones, the organisation's chief executive said agencies had to up their game because of the often lawless areas in which they worked.
He told an audience at the Institute for International & Strategic Studies (IISS): "If you are in the position of gatekeeper to aid you have enormous power in relation to those people.
"The corollary of that enormous power ought to be a very highly developed sense of responsibility and duty to provide proper protection.
"It's clearly the case that there are failures of protection that have happened.
"You can say those failures have happened because we are operating in tough environments, in conflict-affected areas, in areas where there is no rule of law, there is no functioning politics, and because of that somehow lower standards should apply.
"Actually that is totally the opposite of the truth. It is precisely because you are operating in those environments that you have, with those people with that level of vulnerability, you should be applying higher standards.
"We need to be investing more in our safeguarding and protection systems and we have been."
Save The Children is one of the charities which has been rocked by scandals in recent weeks and has launched an independent review.
In February, former chief executive Justin Forsyth resigned as deputy executive director of Unicef in New York after admitting making "some personal mistakes" during his time at Save The Children.
Mr Forsyth was twice subject to investigation at Save The Children after concerns were raised about his conduct in 2011 and again in 2015 involving three women.
The charity has since apologised to the female employees, admitting their claims were not properly dealt with at the time.
The disclosures came after Brendan Cox, the widower of murdered MP Jo Cox, admitted that he made "mistakes" and behaved in a way that caused some women "hurt and offence" when he was working at Save The Children.
Mr Watkins, who took over as chief executive in September 2016, said it was a "critical time" for aid charities, adding: "Being defensive or burying our heads in the sand is not the smart thing to do.
"A lot of the press coverage of our organisation and other organisations in the sector has been very uncomfortable over the last month.
"But we owe the journalists who have done these investigations a debt of gratitude actually, because they have turned a spotlight on things that need to be addressed."
Save The Children was among more than 20 charities, including Oxfam Great Britain, Unicef UK, Muslim Aid, Cafod, Christian Aid, and WaterAid, which last month pledged to boost safeguarding and called on people to report unacceptable behaviour.
Mr Watkins, who previously worked for the United Nations, spoke while launching The War On Children, a report highlighting crimes against children in war zones around the world.
He added: "There are things I have read about, things that I have heard from our staff that disturb me and things that are not acceptable.
"I hope I have signalled very clearly since I started as CEO that I have a zero-tolerance approach to any sort of bullying or sexual harassment.
"It is not going to happen on my watch but we do have an issue and we have a legacy that I have to deal with."