Some lecturers at universities in Northern Ireland are beginning 14 days of strike action on Thursday.
The action by University and College Union (UCU) members is due to a long-running dispute about pay and pensions.
While there are more than 1,500 UCU members across both Northern Irish universities not all are expected to walk out.
Disruption to some classes and lectures at Queen's University in Belfast and Ulster University is expected.
Strikes are also taking place at 74 other universities across the UK.
That includes the Open University, some of whose staff in Northern Ireland are also taking industrial action.
The UCU has said its members - both academic and support staff - will strike on:
- Thursday 20 and Friday 21 February
- from Monday 24 February to Wednesday 26 February
- from Monday 2 March to Thursday 5 March
- and they will then walk out for the entire week beginning Monday 9 March
In an email to all students at Queen's University, pro-vice chancellor Prof David Jones said the university would remain open during the strike action.
He said that Queen's University respected the right of staff to take industrial action but as the dispute was a national one the university could not resolve the central issues on its own.
"We expect the impact of the action to vary across the university and to be very limited in some areas," he said.
"Many students will not be affected at all."
Prof Jones also said the university would make "every reasonable effort" to ensure that students would not be disadvantaged if their lectures were cancelled.
"I would like to assure you that, as far as possible, material that has not been delivered as a result of industrial action will not be assessed," he added.
Prof Paul Bartholomew, the deputy vice-chancellor at Ulster University, gave a similar message in an email to students.
"Whilst any strike is regrettable, we respect the right of staff to take part in mandated industrial action and recognise that this decision is not taken lightly by colleagues," he said.
"We are making preparations to minimise any potential disruption on our campuses and we will also take steps to ensure that students whose studies may be affected by the strike are not disadvantaged at the point of assessment."
UCU members at both universities walked out for eight days in November and December last year alongside colleagues at 60 universities across the UK.
Caitlin Adams, the UCU branch president at the Open University in Northern Ireland, said universities were not tackling job insecurity, workload, pay and pension issues.
"We'd rather be teaching but the employers have failed to offer meaningful measures to improve conditions and pay," she said.
"UCU is ready to negotiate: employers need to come up with a fair settlement for our disputes."