Bridget Warr, chief executive of the Guide Dogs for the Blind Association, has announced that she will step down next year after six years in the role.
Warr, who was appointed at the end of a restructuring process in 2004 after the charity lost £20m on the stock market, will leave the charity in March.
In a statement, she said she was leaving the charity so that a new chief executive could lead it in delivering its new 10-year strategy.
"It will be a huge wrench to leave Guide Dogs, but I believe the time is right for both me and the organisation to move on," she said.
"I am proud of the achievements we have made in delivering the last five-year strategy, particularly extending our mobility services and achieving changes in the law to uphold the rights of blind and partially sighted people," she said.
A spokesman for Guide Dogs said it had not yet appointed a new chief executive and would open the post for applications on 13 September. He said the charity hoped the new chief executive would work alongside Warr before she left.