She is survived by a sister, two nieces and two nephews.

Johnston retired from Grey in April 2000 after a career that spanned four decades. Her husband, Timothy Joyce, a founder of Mediamark Research Inc (MRI), died in 1997 after a long illness.

“Hers was a presence and personality not to be forgotten once encountered,” said Alain Tessier, a founder and chairman of MRI. “Her wit and wisdom about life in general infused the practice of her profession, and should cause her to be a model for how it should be done. Those of us in the business who knew her well, or even at all, have reason to mourn her passing. There are many more whose lives she touched who will mourn as well.”

An acknowledged leader of the media research community, Johnston was elected chairman of the Agency Media Research Council three times. She served for three years as chairman of the Media Research Committee of the American Association of Advertising Agencies, was president of the Radio TV Research Council and worked on a number of research committees of the Advertising Research Foundation.