Sandy Johnson attended the University of Pennsylvania, CIDOC in Cuernavaca, Mexico, and the New School for Social Research in New York City. She studied acting at the Neighborhood Playhouse in New York and at the Actors Studio in Los Angeles.

As an actress, Johnson appeared in numerous regional stage productions, and on TV, a running part in Search For Tomorrow, guest appearances on Mannix, Ironsides, Mission Impossible, and in the feature films Ash Wednesday and Two-Minute Warning.

Screenplays include Summer’s Gold, and The Girl Scouts, and TV episodes for Norman Lear.

In 1979, Johnson published her first novel, The Cuppi (Delacorte/Dell), a fictionalized account of a twelve-year-old runaway. The first book to deal with the rising epidemic of teen-aged children taking to the streets, The Cuppi (a police acronym for Circumstances Undetermined Pending Police Investigation) was a Literary Guild Selection. Because of the extensive research involving interviews with dozens of runaways, Johnson was called upon to lecture to parent-teacher groups, and law enforcement and social agencies, and made numerous TV appearances: Washington and Philadelphia morning shows, Good Morning America, The Mike Douglas Show, among them.

As a result of her personal crusade, sections of the book were read into the Congressional Record, and twelve crisis shelters opened in major cities. Stories appeared in newspapers and magazines around the country, including a four-page spread in People Magazine. Features ran in Newsday, San Francisco Chronicle, Wall Street Journal, Liz Smith's column, and received rave reviews in The New York Times, Publishers Weekly and the Wall Street Journal. The Library Journal featured Johnson's photograph on its cover. The Cuppi was published in four languages.

Johnson’s second novel, Walk A Winter Beach (Delacorte/Dell 1982), which The New York Times included on its Notable Books of the Year list:

"Walk A Winter Beach primarily concerns the quest of an honest cop for his wife's killer, so it can be classified as a police procedural. But it has much more to offer than the routine procedural, what with a moral crisis, a romance, a Mafia element, some unusually well-drawn types and a lot of activity in Montauk, L.I.

"The hero is Jake Ryan, a lieutenant in the New York Police Department. He is smart but not obnoxiously so, literate but not learned, brave but not foolhardy. In short he is a real person rather than a collection of supreme virtues. That is typical of Ms. Johnson's approach toward her characters. She tries to see them whole, and for the most part she succeeds. Even the Mafia fellow, an elderly Jewish man with a great deal of charm and lots of quaint, old fashioned notions, emerges as a believable and unusual character in his own right."

Crime, Newgate Callendar, New York Times

Against The Law (Bantam 1986), a non-fiction account of the Knoxville, Tennessee attorney Mary Evans who fell in love with her convict-client and aided his escape from prison.

In recent years Johnson’s work with Native Americans produced The Book of Elders: The Life Stories & Wisdom of Great American Indians (HarperSanFrancisco 1994) and with Tibetans for The Book of Tibetan Elders (Riverhead 1996).

In 1989, Johnson joined the faculty of Washington College in Chestertown, MD, as a creative writer instructor.

Her current book is The Brazilian Healer With A Kitchen Knife and Other Stories of Mystics, Shamans and Miracle-Makers.

Johnson lives in Los Angeles.