The influential British Association of Medical Managers has ceased trading, just days before its annual conference.
Delegates for its conference in Brighton this week were emailed last Friday that it was cancelled.
They had paid around £1,000 for the conference, which was to be addressed by NHS chief executive Sir David Nicholson.
Callers to the BAMM office in Stockport over the weekend heard an answer phone message saying the company was in receivership.
But chief executive Jenny Simpson said that was incorrect and the board had decided to temporarily cease trading “with the utmost and heartfelt regret” while it examined its options.
Professor Simpson said the financial situation in the NHS meant the future for the organisation was very uncertain.
She said: “It is very difficult to run an organisation on the periphery of the NHS when the income streams are very uncertain.
She said BAMM was looking into the possibility of refunds for the conference, but she was unable to say what, if any, were the extent of its debts.