Dr. Eric Herbst at Duke University is considered one of the founders and leading experts in the field of astrochemistry. In his current research effort, Dr. Herbst will continue a program of theoretical modelling of dense interstellar clouds in which he will incorporate new constituent molecules and the effects of dust grains. Dr. Herbst will also try to understand in detail the individual gas phase processes that occur inside dense interstellar clouds. Primarily through observations at radio wavelengths, observers have detected the presence of more than seventy different molecules in the vast regions of space that lie between the stars. The existence of these molecules has stimulated a large research effort directed towards understanding why the molecules are present and how they are produced. The objective of Dr. Herbst's theoretical research is to better understand the chemistry of this aspect of the interstellar medium.