Atomic, Molecular and Optical Physics was started at Columbia by I.I. Rabi in the 1930s and given a further crucial impetus by the invention of the laser here in the late 1950's. By the 1990's, experiments were demonstrating increasing control over single atom systems, as acknowledged by the 1997 Nobel Prize in Physics ''for development of methods to cool and trap atoms with laser light''. Since then, there has been a rapid increase in the ability to manipulate systems with larger numbers of atoms and to control their quantum states. AMO systems form the basis of many of our most precise measurements and can be used as fine probes of other materials. The ability to manipulate the precise quantum state of thousands of atoms has applications ranging from studying the time dependence of chemical interactions to quantum computing.<br>Condensed matter physics is the largest subfield of physics, its focus is on studying key questions about the origins and nature of matter, where many interacting constituents can combine to produce novel properties, such as how light interacts with the matter. Experimentalists continue to create materials with new properties and with current techniques are manipulating materials at the quantum level. The properties and phase structure of these materials are studied at a variety of temperatures and measured with an ever-increasing diversity of probes. Theoretical insight into the fundamental causes of new properties, as well as first principles predictions of what might be possible, stimulate regular collaboration between experimental and theoretical physicists in this area. New forms of matter may exhibit properties that are useful in devices or they may strain our theoretical understanding of the origin of their properties. The study of matter at the nanometer scale provides one of the main sources of interdisciplinary links between physics and other fields and is a crucial component of the Columbia Nano Initiative.