Environmental problems occur where ecosystems and human social systems converge. As a result, they are not easily resolved by science or technology because they stem from the diversity in human perceptions, expectations, and values. A decisionmaking process known as collaboration offers a method of joint problem solving that is based upon an application of social learning theory. Collaboration is inspired by the concept of participatory democracy and advanced by the exchanges inherent in a civic discourse. It can involve individuals and representatives of agencies, organizations, and other groups in open discussions where the process participants share information and power as they take joint responsibility in attempting to make decisions, reach solutions, or resolve issues. This study identifies basic elements of collaborative environmental decisionmaking through an analysis of several collaborative processes. It then examines how these collaborative processes work and whether collaboration is an effective environmental decisionmaking process. Two case studies are examined: the Chesapeake Bay Program Community Watershed Initiative Workgroup, and the Elizabeth River Project Watershed Action Team. The case studies illustrate that the presence or absence of the identified elements of collaborative environmental decisionmaking affect the results of the process. They also illustrate that the participants in these processes incur changes in the manner in which they regard the issues. Collaborative environmental decisionmaking works by establishing a dialogue among people with disparate positions, concerns, and interests in an attempt to find common ground. The process can link formal, theoretical knowledge with informal, practical wisdom through face-to-face dialogue among contending parties. It can result in social learning and build social capital. / Ph. D.