Systems and methods are described herein for enabling a user of a diagramming system to select elements of a diagram and apply a layout constraint thereto. In accordance with certain embodiments described herein, the systems and methods provide the user with a means to perform these tasks in a manner that is faster, easier and more intuitive than interfaces provided by conventional diagramming systems. For example, in accordance with at least one embodiment described herein, a single user gesture is obtained and the steps of selecting elements of a diagram to which a layout constraint is to be applied and selecting the layout constraint are both performed based on the single user gesture.