Sidney Nagel's work has drawn attention to phenomena that scientists have regarded as outside the realm of physics, such as the science of drops, granular materials and jamming. Another area of emphasis is his attempt to understand the properties of disordered materials. A perfect crystal of a chemical element or a compound is composed of an ordered arrangement of atoms, but in a disordered system-a glass, for example-the atoms are in disarray. Disordered systems also exist on a larger scale, as with the sand grains in a sand pile. Nagel's honors include election to the National Academy of Sciences in 2003 and the American Physical Society's Oliver Buckley Prize in 1999.