Workers manned picket lines outside the DRD offices at Bentrim Road, the Environment Agency at Antrim Road and Bow House in Bow Street as well as other public sector workplaces around the city.
They were all members of NIPSA, Unite, the Public and Commercial Services Union (PCS) and the University and College Union (UCU).
The dispute with the government is over plans to increase the retirement age for public service employees, linking it to the state retirement age.
NIPSA general secretary Brian Campfield said the strike action was “designed to send a clear message to the government that workers will continue to resist attacks on their pensions and on staffing levels”.
The government’s pension plans have been largely inspired by Lord Hutton’s independent inquiry into the rising cost of public service pensions.
He suggested that most staff should pay higher contributions, with the increases being phased in during the next three years.Then, from 2015, most current staff and all new recruits would be offered career-average schemes instead of the more expensive, mainly final-salary, versions now on offer.