Before World War II, the couple travelled in Africa; after Murray's death in 1957 she returned there with her son.
She illustrated a number of Patricia Lynch's Irish books including Long Ears and Orla of Burren.
Joan illustrated all six books of the Ladybird series of The Adventures of Wonk about a koala.
Her work was also commissioned and/or reproduced in the New Zealand School Journal (NZ Department of Education) in the 1950s.
For her version of Arabian Nights (Dent, 1951), she used a formal decorative treatment, while the Aesop's Fables, (Blackwell, 1972) was illustrated in vivid, flat colours.