The United Nations says as many as 70 percent of women around the world will experience violence during their lives - usually at the hands of men they know well, most often their husbands or ex-partners.
Secretary-General Ban Ki-moon urged those involved in his new Network of Men Leaders to use their voices to help end violence against women - be it in the home, on the street or in a war zone.
"Break the silence. When you witness violence against women and girls, do not sit back. Act. Advocate. Unite to change the practices and attitudes that incite, perpetrate and condone this violence."
Mr. Ban said he is launching the campaign not only in his capacity as Secretary-General, but also as a son, husband, father and grandfather.
"Together we must raise public awareness, and boost political will and resources to prevent and address all forms of violence against women and girls."
The secretary-general also announced $10.5 million in additional funds to help support 13 initiatives around the world dealing with violence against women.
Several prominent male politicians and activists have signed on to the new initiative. Among them is Nobel Laureate Archbishop Desmond Tutu of South Africa. His country has an alarmingly high rate of sexual violence against women. A recent study there found that a quarter of the male population admitted to rape, and almost half of the respondents admitted to raping more than one woman.
Archbishop Tutu addressed the gathering via a videotaped message:
"You are a weak man if you use your physical superiority to assault and brutalize women. A society that permits violence against women is a society on the way out."
Violence against women occurs virtually everywhere and takes many forms. It can be the obvious brutality of rape, beatings or murder. But it also includes practices such as female genital mutilation, human trafficking, and a woman's inability to practice safe sex and protect herself from being infected with HIV/AIDs. And when women are abused, experts point out, their children also suffer.
The United Nations hopes that if men lead the way in teaching each other that violence against women is unacceptable, it will one day be stamped out.