The Irish Prison Officers Association has expressed growing frustration with what it called the Government's failure to address prison overcrowding.
The issue is set to be discussed at the association's annual conference in Killarney, Co Kerry, in the coming days.
The IPOA says Irish jails are so overcrowded that a revolving-door system is beginning to emerge, with inmates released early to make way for new prisoners.
It says the situation has been exacerbated by the Government's decision to close prisons in the Curragh, Spike Island and Shanganagh without building replacement facilities.
The association has also expressed concerns about Minister for Justice Michael McDowell's suggestion that bail laws may be tightened due to the level of crimes being committed by people on bail.
It says there is no space in Irish jails to deal with the extra prison population that such a crackdown would create.