Party leaders have agreed to implement a new complaints system for staff amid Westminster's sexual harassment scandal.
At a meeting at 10 Downing Street on Monday, leaders of the Westminster parties agreed proposals for an independent grievance process, to be introduced in the New Year, along with improved human resources support.
They have also established a cross-party working group to implement changes.
Their action comes amid a host of allegations against Government ministers, MPs and officials from across parties.
Speaking after the meeting, the Prime Minister hailed an "important step forward" as she revealed the plans, which includes upgrading an existing helpline in order to provide face-to-face support for parliamentary staff by the end of November.
"Sadly over recent days we've seen a number of allegations about figures from across the political parties," she said.
"It's important that those are investigated impartially and some have rightly been referred to the police.
"I think if this hasn't happened to you it's difficult to appreciate the impact this sort of behaviour can have.
"It simply has a lasting impact on people and we need to do more to stop these abuses of power."
Theresa May added the allegations centred around Parliament "should be a matter of shame for us all" but denied having knowledge of claims against Tory MPs before the scandal broke.
She said: "The allegations that have come to the fore in the last week, I've been made aware of over that time period because of things that have appeared in the press but also allegations that I've been told over the last week in private."