Ms Gunn has worked in legal practice for 23 years and was previously a partner at Shepherd & Wedderburn for 12 years.

She moved into the finance sector after being appointed to Ignis Asset Management and was a non-executive director of Airdrie Savings Bank.

She is a member of the independent governance committees of Phoenix Life and Standard Life, a member of the accounts commission and chair of Wheatley Solutions.

For the past five years, Ms Gunn has been on the board of Wheatley Group.

Ms Gunn is also on the board of the Chartered Banker Institute and on the ethics board of the Institute of Chartered Accountants of Scotland.

With 33,000 members, the Scottish Building Society is the world’s oldest mutual member-owned society, having celebrated its 170th birthday last year.

Her appointment to the board arrives after Paul Denton was appointed chief executive in June and former Barclays Ireland chief Andrew Hastings was appointed as non-executive director.

Ms Gunn said: “I am delighted to join the Scottish Building Society’s board in a non-executive role. I look forward to bringing my knowledge and experience to the board.”

Raymond Abbott, chairman of Scottish Building Society, said: “We are pleased to welcome Sheila to the board of Scottish Building Society. Her experience across the finance sector and working with housing associations means she brings strong experience and expertise to the board.”