This paper examines the application of passive vibration control methods to a simplified satellite boom. It is suggested that such methods may allow an efficient means by which to control structural vibrations. In this research, an initial structure is designed having a regular, repeating geometric pattern. This design is then modified using a genetic algorithm (GA), which is one of a number of recently developed evolutionary computing methods. Here the GA changes the geometry of the design by altering the three-dimensional coordinates of its joints. The aim is to minimize the band-averaged noise transmission along the boom. This paper shows that by altering the geometry in this way, significant improvements in the structure's noise performance can be achieved. While this research is far from complete, the work outlined demonstrates the potential usefulness of this approach for controlling structural vibrations.