The Prison Officers' Association has accused the Prison Service of ignoring the activities of criminal gangs in prisons.
At the association's annual conference in Galway, prison officers are expected to say the capacity of gangs to operate in prison is enhanced by overcrowding.
POA President Stephen Delaney has called for an independent review of the development and behaviour of gangs in prison to identify how they can be dealt with.
The presence of gangs in society is reflected in the prisons where approximately ten gangs use violence and intimidation against other inmates, control the drugs trade, liaise with associates outside and continue inter-gang feuds.
The association says prison gangs are active, vicious and cause immense difficulties within the prison system.
It says they create an unsafe situation that can have dreadful consequences.
Mr Delaney said compliant prisoners are terrified by these gangs.
He accused the Prison Service of ignoring them and leaving individual prison officers to work on the problem, day by day, issue by issue.
Mr Delaney called on Minister for Justice Alan Shatter to establish an independent review of the development and behaviour of the criminal gangs, and develop clear, concise and effective recommendations on how they can be controlled.
The Director of the Prison Service told today's conference he will not allow criminal gangs to rule the country's prisons.
Michael Donnellan said that a senior management group assesses the threat from gangland criminals, they are managed and separated, intelligence is gathered and the operational support unit tackles drugs and phone smuggling.
He said: "We are more on top of this issue now more than ever in my belief. We will build on the experience of the last decade."
