The investigative assault upon the enigmatic asphaltenes has recently resulted in sig­ nificant advances in many varied disciplines. Taken individually, each discipline exposes certain facets of asphaltenes, but each, alone, can never reveal asphaltenes from all van­ tages. Even seemingly narrowly focused issues such as the molecular structures of asphal­ tenes, or the colloidal structures of asphaltenes require a confluence of many lines of investigation to yield an understanding which differs from truth by diminishing uncer­ tainty. An holistic treatment of the asphaltenes is a powerful approach to evolve further their understanding. For example, examination of asphaltenes at the highest resolution yields molecular structure. A slight increase in scale probes asphaltene colloidal structure. Weaving together asphaltene studies performed at different length scales results in a fabric which envelops an encompassing vision of asphaltenes. At the same time, the interfaces of these hierarchical studies provide additional constraints on imagination, more than investi­ gations at individual length scales alone. These considerations shaped the timing, format, and the content of our book. The editors are very appreciative of the diligence and hard work manifest in each of the contributed chapters herein. We thank the contributing authors for making this project a success. Oliver C. Mullins Eric Y. Sheu vii CONTENTS I. Asphaltenes: Types and Sources ...................................... .