Greg grew up in Woodbridge, Ontario. He attended the University of Toronto Schools and the University of Toronto, graduating with an Honours B.A. in English in 1968. His first book publication was in TO Now (House of Anansi, 1968), an anthology of young Toronto poets, edited by Dennis Lee. After an M.A. in English at the University of Toronto, Greg lived in the U.K., where he completed a Ph.D. at the University of London, on the philosopher George Berkeley.
Greg has published eighty stories and essays in magazines and anthologies in Canada, the U.S., and the U.K. His first story collection, Famous Players (Coach House), edited by Matt Cohen, appeared in 1982. His second and third books—the story collection White Buick (Oolichan) and the novel Spin Dry (Mosaic)—appeared in 1992. His third story collection The Roaring Girl (Somerville House 1995) appeared in Canada, the U.K., the U.S., Germany, and China. His second novel, The Healer (A Phyllis Bruce Book/HarperCollins 1998) was the first title to appear under the HarperFlamingo imprint in Canada, the U.K., and the U.S. His third novel Bedlam (A Phyllis Bruce Book/HarperCollins) was published in 2004 in Canada and the U.S. and a fourth story collection, Act Normal (Anansi) in 2015.
Greg taught at the University of Alberta for thirty years and is now Professor Emeritus. From 1999 to 2017 he directed the Writing Studio at the Banff Centre. In 2011-12 he served as Chair of the Writers’ Union of Canada. He currently lives and writes in Toronto, with his wife Rosa Spricer, a psychologist in private practice, now retired. He and Rosa have one son, David, who teaches at MacEwan University in Edmonton.