The National Trust for Scotland is searching for a new chair after Shonaig Macpherson decided not to seek a second term.
Macpherson, an intellectual property lawyer, has been chair since 2005, but will stand down when her current appointment ends in 12 months' time.
"Over the next 12 months a major review of the trust's governance structure and its future role in looking after Scotland's heritage is to be carried out," she told a meeting of the trust's board in Edinburgh. "In terms of timing it makes sense to seek a new chair to coincide with this review rather than later next year when the review will be almost complete."
Macpherson has enjoyed an eventful tenure as chair. Chief executive Mark Adderley resigned in September 2008, just 18 months after his appointment, and the trust announced the cutting of more than 90 jobs in March, about a fifth of its workforce.
She also clashed with the trade union Prospect, which claimed that the £21m Robert Burns Birthplace Museum project could lead to the organisation's collapse. Instead, she attributed financial problems to outdated practices that were failing to attract visitors to the trust's properties.
But Macpherson said the trust's financial position had improved and both visitor numbers and membership had increased. "I am enormously proud of what we have achieved over the past four years," she said.
A selection panel will identify potential candidates for the position. A nominations committee will interview shortlisted candidates and put forward a single candidate for approval by the trust's council.