Donald Sidney Appleyard was born on July 26, 1928, in London, England.

He was an English American urban designer, theorist, author, and educator. He studied architecture and later urban planning at the Massachusetts Institute of Technology. After graduation, he taught at MIT for six years and later at the University of California, Berkeley. He worked on neighbourhood design in Berkeley and Athens and citywide planning in San Francisco and Ciudad Guyana. Appleyard gave lectures at over forty universities and acted in a professional capacity in architecture and planning firms in the United Kingdom, Italy, and the United States. He is the author of several books and papers, e.g., "The view from the road" (1964), "The Conservation of European Cities" (1979) and "Livable Streets" (1981). In 2009, he was named number 57 of Planetizen's Top 100 Thinkers.

He died on September 23, 1982, after a traffic collision in Athens, Greece.