Born in 1930 in Barnes, London, Ayres had already decided by the age of fourteen that she wanted to become an artist. From 1946-1950, she attended the Camberwell School of Art, and later ran the AIA Gallery with her future husband, painter Henry Mundy. She taught at the St. Martin's School of Art in London from 1965-1978 and served as Head of Painting at the Winchester School of Art from 1978- 1981.
Ayers first exhibited with “Young Contemporaries” in 1949 and with the London Group in 1951. In 1956 she had her first solo exhibition at Gallery One in London and subsequent one-man shows were held regularly at galleries in London, throughout the United Kingdom and in Europe.
Among Ayres’s many awards are the Japan International Art Promotion Association Award in 1963, the Arts Council of Great Britain Bursary in 1975, the Arts Council of Great Britain Purchase Award in 1979, the Second Prize at the John Moores Biennale in Liverpool in 1982, the Blackstone Prize from the Royal Academy of Arts in 1988 and 1990 and the Charles Wollasten Award from the Royal Academy of Arts in 1989, among others.
Ayres was made an Honorary Doctor of English Literature by London University in 1994, a Senior Fellow of the Royal College of Art in London in 1996 and she received a Sargent Fellowship from the British School at Rome in 1997.