This paper presents a framework for evaluating mechanisms that involve the public in environmental decision-making. These include traditional participatory mechanisms--such as public hearings, notice and comment procedures, and advisory committees--as well as those considered more innovative--such as regulatory negotiations, mediations, and citizen juries. The framework is based on a set of "social goals," defined as those goals which are valued outcomes of a participatory process, but which transcend the immediate interests of any party in that process. The goals are: educating the public, incorporating public values and knowledge into decision-making, building trust, reducing conflict, and assuring cost-effective decision-making. The paper begins with a discussion of the need for an evaluative framework which 1) identifies the strengths and weaknesses of a number of different participatory mechanisms, 2) is "objective" in the sense of not taking the perspective of any one party to a decision, and 3) measures tangible outcomes. Section One presents the social goals framework as an approach for meeting these objectives. It illustrates how the framework can be applied to one case study in environmental decision-making: the performance of the Restoration Advisory Board at the Fort Ord military base in California. In Section Two, we contrast the social goals framework with two alternative approaches to evaluation, one based on participatory processes and one based on stakeholder interests. We find that, while useful for answering some questions about public involvement, these two approaches fail to meet all three objectives and may miss important information about the success of a particular participatory effort. In Section Three we take a closer look at participatory mechanisms and discusses how each is likely to perform against the various social goals.