"awareness" of the world's citizens and encourage governments to devote more attention and resources to address this issue. The series editors thank the international panel of contributors for bringing this timely series into completion. We also wish to acknowledge the very insightful input of the following colleagues: Prof. A. L. Page of the University of California, Prof. T . C. Hutchinson of the University of Toronto , and Dr. Steve Lindberg of the Oak Ridge National Laboratory. We also wish to thank the superb effort and cooperation of the volume editors in handling their respective volumes. The constructive criticisms of chapter review­ ers also deserve much appreciation. Finally, we wish to convey our appreciation to my secretary, Ms. Brenda Rosier, and my technician, Ms. Claire Carlson, for their very able assistance in various aspects of this series. Aiken, South Carolina Domy C. Adriano Coordinating Editor Preface to Acidic Precipitation, Volume 5 (Advances in Environmental Science) Acidification research has been ongoing for several decades. It was not until the 1980s, however, that scientists began to recognize the complex­ ity of the factors causing the decline in forest growth and deterioration of fish populations in acidified lakes. The general feeling, based on correla­ tive research, was that long-range transported air pollution was the main cause. Proof, however, was difficult to obtain because of complex interac­ tions of various stress factors including natural ones.