More than 90% of Scotland's civil servants have taken part in strike action over job cut plans, unions said.
Civil servants say the proposed job cuts could hit vital services
The stoppage is said to have affected benefit offices, Edinburgh Castle, the Scottish Executive and the Inland Revenue centre in East Kilbride.
The Public and Commercial Services Union's Scottish secretary Eddie Reilly said the action sent a "clear signal" to Chancellor Gordon Brown.
But the executive said it was not aware of any disruption to its services.
"All Scottish Executive offices are open," a spokeswoman said.
The Department of Work and Pensions said 52 of its 168 job centres and social security offices in Scotland were closed.
Of those which were open, 84 had a reduced service, nine suffered severe disruption and 24 were unaffected.
A pensions processing centre in Dundee was operating normally but was unable to take phone calls from the public.
The Falkirk office of the Child Support Agency was still operating after 360 of its 1,470-strong workforce took
part in the stoppage.
The National Gallery of Scotland was closed by a security staff strike, while only the ground floors of the Scottish National Gallery of Modern Art, the Scottish Portrait Gallery and the Dean Gallery were open.
The PCS said picket lines were in place outside every government office in Scotland. Its reports suggested that more that 90% of its 30,000 members were on strike.
Outside Edinburgh Castle, half a dozen union members handed out leaflets to passers-by and waved banners saying: "I'm not a skiver, I'm a striker."
Protester Kerstine Hillary, a full-time union representative, said she thought her own job was under threat.
She said unions were willing to work with departments to make efficiencies, but did not want an "arbitrary cut".
"We are getting a fantastic response from our colleagues," she added.
"I've been a civil servant for 15 years and I know people that have been in the civil service for longer and have never been out on strike before that are actually standing on picket lines today.
"But the biggest problem we've got is that the public don't actually realise what's going on."
Mr Reilly said: "Our members have clearly shown from their response today that their determination to continue this campaign to reverse the chancellor's decision to cut over 100,000 jobs and continue the fight to protect their pensions and the services they deliver.
"This will send a clear message to the chancellor and the UK Government that our members are prepared to stand up and fight for what they believe in."
However, Mr Brown has said that the action will not prevent him from pursuing his proposed cutbacks across the civil service.
"Our decisions mean more police, more teachers, more doctors and more nurses," he said.
"We will provide help with information, relocation and retraining to help staff move into front line work within the public sector, but we will not be diverted from these necessary changes so that we can make this essential investment."
The 24-hour strike is part of a UK-wide protest against the proposed job cuts.
The union balloted nearly 300,000 members for a one-day strike on 5 November.
The Cabinet Office said it was disappointed at the strike and that it was taking essential efficiency measures across the public sector.
"Maintaining services to customers is a priority for all departments and agencies. Departments have contingency plans in place to mitigate the impact of the one-day strike," it said.