How many movies have D.W. Griffith and Lillian Gish collaborated on?

They have worked on 20 movies together! Their first movie together was Judith of Bethulia (1914) while their highest rated movie together was Intolerance: Love's Struggle Throughout the Ages (1916). They have not worked together since D.W. Griffith - Years of Discovery 1909-1913 (2002). They are most known for their drama films together.