ELSEVIER MANAGING THE EIA PROCESS Public Participation in Impact Assessment: A Social Learning Perspective Thomas Webler Wendell, Massachusetts Hans Kastenholz Institute for Behavioral Science, Ziirich, Switzerland Ortwin Renn Center of Technology Assessment in Baden-Wiirttemberg, Stuttgart, Germany This paper is a contribution to the development of normative criteria for evaluating models of the participation process. The concept of social learning is described and an effort to show how communities of people with both diverse and common interests can reach agreement on collective action to solve a shared problem. The authors have developed the idea of "cooperative discourse" as a method to achieve consensus. The authors utilize the case study of the siting of a municipal waste disposal facility in the eastern region of the Canton of Aargau in Switzerland, to demonstrate the applicability o f'cooperative discourse". They argue that successful public participation must yield not only fair and competent decisions, but also uncover common needs and understandings that transcend egoistic aims, and contribute to the development of democracy. Introduction There are three main reasons why environmental and social impact assess- ments include opportunities for public participation. First, the competence of the final decision is higher when local knowledge is included and when ex- Address requests for reprints to: Thomas Webler, 132 Farley Road, Wendell, MA. An earlier version of the paper was presented at the Society for Human Ecology 7th Meeting, East Lansing, MI, USA April 22, 1994. ENVIRON IMPACT ASSESS REV 1995;15:443-463 © 1995 Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010 0195-9255/95/$9.50 SSDI 0195-9255(95)00043-E