Spies at Work (German: Spione am Werk) is a 1933 German thriller film directed by Gerhard Lamprecht and starring Karl Ludwig Diehl, Brigitte Helm, and Eduard von Winterstein. A spy film, it is set during the First World War conflict between Austria and Italy.

The film's sets were designed by the art director Karl Weber and Erich Zander. The film was shot at the Babelsberg Studios in Berlin. A British version On Secret Service was also made.