The armed forces healthcare agency is to lose its chief executive early next month - shortly before the findings of a radical review of military hospitals are made public.
Former NHS manager Ron Smith was appointed chief executive of the Defence Secondary Care Agency when it was set up in April 1996, and has been a key figure in the strategy review begun last October.
Mr Smith, a former health authority chief executive, was not available for comment last week and the reasons for his sudden departure are unclear. He had been expected to stay to see through the review's implementation.
It is thought that his successor is likely to be a uniformed officer rather than another civilian manager from the NHS.
Informed sources said the feeling within the DSCA was that an earlier objective of bringing military hospitals up to NHS standards had now partially been achieved, making it possible for the service to revert to military control.
Mr Smith spent 20 years in the RAF, but is viewed as a civilian. 'Military doctors need a military ethos, ' a DSCA spokesperson said.
Confusion marked Mr Smith's departure last week. At one point he had agreed to stay until mid-August to complete a special project for the surgeon general.
The review of the£100m-a-year service follows a Commons defence committee report which concluded that the defence medical services were not robust enough to support front-line military needs. It is yet to be published.