Sidney Gilliat (February 15 1908 - May 31 1994) was an English film director, producer and writer.

He was born in the district of Edgeley in Stockport, Cheshire. In the 1930s he worked as a scriptwriter, most notably with Frank Launder on The Lady Vanishes (1938) for Alfred Hitchcock, and its sequel Night Train to Munich (1940), directed by Carol Reed. He and Launder made their directorial debut co-directing the home front drama Millions Like Us (1943). From 1945 he also worked as a producer, starting with The Rake's Progress, which he also wrote and directed. He and Launder made over 40 films together, founding their own production company Individual Pictures. While Launder concentrated on directing their comedies, most famously the four St Trinian's School films, Gilliat showed a preference for comedy-thrillers and dramas, including Green for Danger (1946), London Belongs to Me (1948) and State Secret (1950).

Sidney Gilliat, the English director, screenwriter, and producer, was born on February 15, 1908 in Edgely, Cheshire, England. He began his screen-writing career in the silent movie era, writing inter-titles, going uncredited for his contributions to Adam's Apple (1928), Champagne (1928), and Week-End Wives (1929). He first entered into a working relationship with director Alfred Hitchcock (I) on Manxman, The (1929), for which he did uncredited research. Ten years later, he would help write the dialog for the director's Jamaica Inn (1939). He eventually became a credited screenwriter in the 1930s, with Gentleman of Paris, A (1931). He partnered with Frank Launder, whom he first worked with uncredited on Under the Greenwood Tree (1929), and together they wrote, directed and produced almost 40 movies between their first credited collaboration Facing the Music (1933) through Great St. Trinian's Train Robbery, The (1966), which they also co-directed. For Hitchcock, they co-wrote the classic Lady Vanishes, The (1938). They also wrote Night Train to Munich (1940) for Carol Reed (I). Their collaboration is most famous for generating the St. Trinian's films, most notably Belles of St. Trinian's, The (1954), which was directed by Launder and featured a tour de force performance by Alastair Sim. Sim was also the star of their Green Man, The (1956), for which they received second straight Best British Screenplay nomination from the British Academy of Film and Television Arts. Sidney Gilliat died on May 31, 1994 in Wiltshire, England. He was 86 years old.