Staff at universities across the North West will begin two days of strike action later in disputes over pay, conditions and pensions.
Further industrial action is threatened over the coming months if agreements cannot be reached.
Up to 43,000 members of the University and College Union (UCU) at universities throughout the North West and the rest of the UK will walk out, disrupting lectures students.
The number of universities being hit by the action is the largest since 2016.
There was an eight day walkout before Christmas.
But this latest round - up to to 14 days - means the total number of walkouts will be 22 by March.
University of Manchester
University of Liverpool
University of Lancaster
Edge Hill University
Liverpool Hope University
Liverpool Institute of Performing Arts