While the #MeToo era has paved the way for more victims of sexual harassment to speak up about their experiences, many males aren’t stepping up, said Target (TGT) CEO Brian Cornell.

“Amid sexual harassment claims, what male advocates can’t do is step backwards. I’ve heard too many whispers from men: ‘I’m not going to meet one-on-one with women’ or ‘I’m not going to travel with women.’ That’s one of my single biggest concerns right now,” said Cornell at a conference hosted by Catalyst, a global nonprofit that promotes inclusive workplaces for women in New York City, on Tuesday. “Some of these issues are surfacing, but we have to continue to move forward as we continue to see the advancement of women across America.”

The #MeToo movement is cascading throughout Hollywood, Silicon Valley, Washington and the world of professional sports.

In October, Harvey Weinstein was fired from The Weinstein Company after dozens of women accused him of sexual harassment and assault. Cornell’s statement comes during a reckoning for high-profile executives in corporate America, which had remained out of the #MeToo limelight until recently.

Just last week, two Nike (NKE) executives exited the company after reports that they had protected male employees who mistreated women. Last month, Steve Wynn resigned as chairman and CEO from his namesake Wynn Resorts (WYNN) after accusations surfaced. And Lululemon (LULU) CEO Laurent Potdevin left the athleisure company, after “falling short of standards of conduct.”

‘We can’t put the car in reverse’

Cornell, who joined Catalyst’s board of directors in 2016, addressed the handful of men among the room of 800 attendees, a majority of whom were women, with a simple message.

When men alter their behavior out of fear, they are hindering any advancement in gender equality in the workplace, according to Cornell. That means men have to make an effort to gain the trust of their female colleagues or speak up when they witness injustice.

“Be respectful, be a good person, and know where those lines have to be drawn. You need to develop great relationships [with female colleagues],” said Cornell. “We have to continue to make sure we’re making progress. One of the things we can’t do is put the car in reverse. We need a zero-tolerance policy, good judgment and good values, but we have to continue to move forward.”

Melody Hahm is a senior writer at Yahoo Finance, covering entrepreneurship, technology and real estate. Follow her on Twitter @melodyhahm.

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