House of Commons staff and trade union representatives are to join Theresa May and other party leaders in attempting to crack down on sexual harassment and bullying by MPs.
Westminster's Members and Peers Staff Association (Mapsa), which represents secretaries, and the Unite trade union, which represents researchers, will help draw up new grievance procedures.
Their involvement in the Commons sleaze crackdown was agreed at a meeting between the two groups and the Prime Minister, 24 hours after she met political party leaders.
Unite also claimed the PM had agreed to consider its branch's call for formal recognition at Westminster, which Jeremy Corbyn and Labour MPs demanded at the meeting of party leaders.
Downing Street said the Prime Minister's aim was to have an "open and candid" meeting with Commons staff and hear first-hand their views about the current system of dealing with complaints.
Five Mapsa members and five from Unite met the Prime Minister in her Commons office.
During the talks, she invited their groups to join the working group of senior MPs of all parties which will draw up a new grievance procedure for staff, to deal with misconduct allegations.
"We are to be represented all the way through this, which I think is exactly as it should be," Georgina Kester, a Commons secretary who chairs Mapsa, told Sky News after the meeting.
"It was an extremely constructive meeting. We came away feeling the Prime Minister had listened to us and taken our concerns on board. We have been invited, with Unite, to take part in the working group."
Ms Kester said she was now confident that real progress could be made in curbing sexual harassment and bullying at Westminster. "Everyone is singing from the same hymn sheet now," she said.
"Everybody wants a workable solution to this problem. The involvement of staff at all levels will help. We are a cross-party organisation. I things will change and the situation will improve."
Unite parliamentary branch chair Max Freedman, said: "This was a productive meeting and the Prime Minister agreed to consider the branch's call for formal union recognition.
"Unite also emphasised the need for the voice of staff to be amplified in the discussion of new processes and in eliminating the culture of bullying and harassment.
"We look forward to a positive response from our meeting."
Speaking before the meeting with Mapsa and Unite, the PM's spokesman said: "She feels it is important to get that first-hand sense of the current system.
"We want people to feel they can be open and candid with the Prime Minister. Clearly we want to move forward on a cross-party basis. It will be helpful to inform that to talk to the actual staff."