More than two thirds of BBC staff have witnessed workplace bullying, a shock new report has found.
The Respect At Work review said senior bosses were seen as "untouchable" due to their position within the corporation.
Responding to it, the National Union of Journalists said there was an "institutionalised problem" with bullying at the BBC, with junior staff scared to speak out for fear of "rocking the boat."
Bosses at the BBC admitted the report, by barrister Dinah Rose, made "uncomfortable reading". The 80-page review was one of a number set up in the wake of the Jimmy Savile scandal
Unions said bullying was an 'institutionalised problem' at the BBC
Of 500 people interviewed, more than two thirds said they had witnessed or encountered bullying in the corporation.
"Throughout our conversations we heard a strong undercurrent of fear; fear of speaking out, fear of reprisal, fear of losing your job, being made redundant, fear of becoming a victim, fear of getting a reputation as a troublemaker and not getting promoted if an employee, or further work if a freelancer, supplier or contractor," the report said.
Michelle Stanistreet, general secretary of the NUJ, welcomed action to tackle bullying, adding: "It is quite clear that bullying has become an institutionalised problem at the BBC, one that has taken hold over many years.
"The report's findings underline the fear factor that exists, particularly for those staff on freelance and short-term contracts, who know that speaking out and rocking the boat could damage their career prospects.
Director General Tony Hall said the report made 'uncomfortable reading'
"Many see that bullies have been allowed to get away with shocking behaviour right under the noses of senior management, so have no faith that complaining will bring any redress."
The NUJ said its submission to the corporation demonstrated the "overwhelming scale" of the problem.
Stanistreet claimed the union had amassed 'eye-watering' testimonies of bullying, including people being picked on because of their sexuality, race, sex and age, as well as those "whose lives have been made unbearable for no discernible reason.
"People have been picked off simply because their face doesn't seem to fit."
The report said bullying was much more common that sexual harassment and was "visible, frequent and consistent enough to be a very real concern".
And it said that people had expressed fears that when they had tried to raise issues informally they felt they had been "swept under the carpet".
The review was set up after the Savile scandal erupted last year, alongside an inquiry into the culture and practices of the BBC and another into the decision-making process which led to a Newsnight item probing the DJ's activities being dropped.
Lucy Adams, director of BBC Human Resources, said the report took an "unflinching" look at life in the corporation, and said bullying needed to be dealt with.
BBC director general Tony Hall said in a message to staff: "Parts of this report do however make uncomfortable reading. We need to be honest about our shortcomings and single minded in addressing them.
"I want zero tolerance of bullying and a culture where people feel able to raise concerns and have the confidence that they will be dealt with appropriately."
Announcing an overhaul of PR policy, he added: "The measures we are taking today, including the removal of so called 'gagging clauses', show our commitment to change. This agenda will be a priority for the senior management team going forward."
BBC Trust chairman Lord Patten said: "Sexual harassment and bullying have no place at the BBC and should be acted on and stamped out.