2016
co-directors of The Institute, during the preparation of this article in Heidelberg. I also acknowledge with pleasure the high level of professional assistance provided me in my research by Frau Petra Weiler, United Nations Documents Librarian, at the Institute Library and Mr. Joachim Schwietzke, the Institute Librarian-together with the helpful insights of Dr. Lothar Gundling and Dr. Peter Macalister-Smith. It is an added pleasure to recognize the research assistance of Vincent J. Petrozzo, a former student, for his efforts relative to the consideration of interstate domestic actions for transboundary pollution. Naturally, the views and positions which I have taken in this article are solely my own. "The acid rain problem is in many respects so subtle, and the research so new and complex, that a clear picture of its nature and precise impacts will probably not be available for many years." ' Mostafa K. Tolba, Director of the United Nations Environmental Programme, observed that there are basically two aspects to current environmental concerns over transboundary pollution: determination by consensus of the likely effects specific pollutants have on the environment; and acceptance of legal responsibility for causing either a direct or indirect release of those pollutants.' There are three major ways to reduce the sulfur oxide content of combustion gases: by using fuels which have low sulfur content, by desulfurizing fuels before they are burned or by desulfurizing stack gases