The Third US/Mexico Symposium on Atomic and Molecular Physics brought together forty-five leading investigators in many fields. Both theory and experiment were well represented. The papers in this volume are based on the participants' invited talks at the symposium and represent an important collection reviewing the most up-to-date work in the different fields. The diversity of research areas represented, coupled to a common local point, revealed different perspectives on such questions as: How do particles depend on one another? Correlation provides a good starting point, but are there other useful conceptual approaches which will yield a new view of the phenomena and a more complete understanding?The contributions in this volume provide different perspectives and bring together a collection of papers which serve as a basis for further progress in this field.