Intelligence officer and college head, was born at Mayfield, Vale Road, Claygate, Surrey, the first child of John Alexander Park (1876–1952) and his wife, Doreen Gynneth, née Cresswell-George (1899–1982).
In 1932 Daphne was shipped off to London, aged eleven, to live with a great-aunt. Owing to the Second World War she was twenty-six before she saw her mother again. She thrived at the Rosa Bassett School, an experimental school in Streatham, which she later regarded as a foundational influence in her life.
In 1940 the offer of a place at Somerville College, Oxford, to read modern languages depended on Park winning a scholarship from Surrey county council. Their offer was conditional on her undertaking to teach on graduation. She turned this down: she was already determined to become a diplomat. They gave her the scholarship anyway.
Park joined the Secret Intelligence Service in July 1948. After a short posting to the UK delegation to NATO in Paris and a Russian course in Cambridge she was posted in 1954 to the embassy in Moscow with the cover of second secretary in chancery
Park retired in 1979 and the following year became the principal of her old college at Oxford, Somerville, where she remained until 1989.
Somerville also provided Park with opportunity for wider forms of public service. Apart from her work as pro-vice-chancellor at Oxford (1985–9), she became a member of the council for Voluntary Service Overseas (1981–4) and of the board of the British Library (1983–9), and a governor of the BBC (1982–7). She chaired the legal aid advisory committee to the Lord Chancellor (1985–91), was a member of the royal commission on historical monuments (1989–94), and made a number of other pro bono commitments. She was made a life peer, as Baroness Park of Monmouth, in the 1990 new year's honours list.