Some years ago, I began work on a history of international environmental law and policy. A central, iconic event in that history is the Trail Smelter arbitration. I decided to visit Trail, British Columbia, and the towns and environs across the border in the United States that were alleged to have been damaged by fumes from the smelter in Trail. The path from Trail down to Northport, Washington, follows the valley of the upper Columbia River. It occurred to me that the trip to the region would be scenic and something the family would enjoy so I consulted a well-known travel guide to the area. It contained a map that highlighted in green the roads in the region that were recommended as particularly scenic. The stretch from Northport to Trail – unlike the roads in adjoining valleys – was not colored green. There, in that absence of color, was proof of the enduring ecological legacy associated with the Trail smelter and the international arbitration it spawned.

It is my pleasure to provide the Foreword to this study of the Trail Smelter arbitration: its history, its current relevance to environmental law and policy, and its possible application to transboundary issues beyond the environmental arena. I regret that other matters prevented me from participating in the inaugural Idaho International Law Symposium that is the foundation of this book. It is thus doubly my pleasure that the writing of the Foreword allowed me early access to the richness of this volume.