More and more people are donating blood - but supply levels remain low.
The Irish Blood Transfusion Service recruited more than 20,000 new donors in 2016 - a 40% increase on 2015.
But the service still struggled to maintain an adequate supply, with hospital demand increasing and several blood groups often only at four days supply.
Chief Executive of the IBTS Andy Kelly is urging people to donate.
"As you say rightly, it is a difficult period for us - the bank holiday weekend we should get through ok because we built up stocks in advance.
"Christmas is difficult, this year it's falling on a Monday, with New Years Day the same day, so we will have a period of about 10 days where donations will be difficult to achieve.
"We would ask people to make a special effort at the end of November, coming into the first two weeks of December to really make an effort and come and donate blood.