Nurses and midwives from around the country will gather in Sligo later for the start of the INMO annual delegate conference.
300 delegates are expected to attend the event, which continues until Friday in the Radisson Blu Hotel.
This is the first in-person conference since 2019, and delegates will debate over 40 motions on issues including cost of living increases, hospital overcrowding, the impact of Covid-19, recruitment and retention.
The Minister for Health Stephen Donnelly will address the conference on Friday morning.
Meanwhile, nurses claim hospital overcrowding has led to an increase in violence and threats towards them.
There were over 3,700 attacks on nurses in the HSE last year and some of the victims will give their personal experiences at the INMO's annual conference in Sligo.
Phil Ni Sheaghdha, general secretary of the Irish Nurses and Midwives Organisation, says the problem is getting worse.