He was responsible for the screenplays of such Hope films as The Princess and the Pirate (1944), Where There's Life (1947), The Great Lover (1949), and Sorrowful Jones (1949), which also starred Lucille Ball.

Other films he wrote and directed include Beau James (1957), The Five Pennies (1959) (for which he won a Screen Writers Guild Award), It Started in Naples (1960), On the Double (1961), The Pigeon That Took Rome (1962), A New Kind of Love (1963), Cast a Giant Shadow (1966), and Yours, Mine and Ours (1968), which starred Henry Fonda and again with Lucille Ball.

Shavelson created two Emmy Award-winning television series, Make Room for Daddy and My World and Welcome to It, and wrote for a dozen Academy Award shows.

He wrote, produced, and co-directed the six-hour 1979 ABC miniseries Ike, based on the World War II exploits of General Dwight Eisenhower.

He was survived by a sister, Geraldine Youcha of Manhattan and New City, New York; two children from his first marriage, Richard of Menlo Park, California, and Lynne Joiner of Washington; and three grandchildren.