From 1900 to the mid 1920s, she mostly collaborated with composer Jerome Kern. Her first collaboration with Kern was the musical, "She’s a Good Fellow", followed by "The Night Boat" (1920), and "Sally" (1920). "The Night Boat" was one of Caldwell and Kern's more successful shows but is generally not considered revivable today. The plots and comedy of their shows don’t satisfy contemporary audiences. Her final credited work was a radio adaptation of the 1933 film (on which she had also worked) "Flying Down to Rio".