Philippa Brophy, who has spent her entire 28-year working life at Sterling Lord Literistic, has been named its new president. She replaces Peter Matson, president of the agency since 1985, who will now become vice-chairman to Lord himself.

Chris Calhoun, with the agency for 10 years, has been named vice-president, and Laurie Liss, who had been working with the Harvey Klinger agency, has come aboard as another v-p.

The agency was founded in 1952 by Sterling Lord and merged with Peter Matson's Literistic in 1985. Its other agents are Claudia Cross, Neeti Madan, George Nicholson, Jim Rutman and Charlotte Sheedy as an affiliate. Among its clients are Dr. Robert Atkins, the Berenstains, A.S. Byatt, Billy Collins, Mary Gordon, Dick Francis, Kent Haruf and Simon Winchester.