AV Browne, the Belfast-based advertising agency, has been placed into administration and has stopped trading.
The firm was originally established in 1926 and has most recently operated from offices in the Cathedral Quarter.
The administrators said the firm had faced a "challenging period" and had been impacted "by a number of external factors".
It is still possible that a buyer could emerge for some or all of the business.
The administrators, James Neill and John Donaldson from financial advisors HNH, said they were "currently conducting an appraisal of the business with a view to establishing its viability".
They added: "This may involve a sale of the business and any parties with an interest should make contact immediately."
 
The administrators said their immediate priority is to communicate with employees, creditors, customers and landlords.