Abstract
Technology assessment has been evolving as a research-based and anticipatory field of scientific policy-advice for more than fifty years. Its position at the interface between science and policy-making has caused several debates on its adequate roles. Proposals reach from the position of a neutral and distant observer of ongoing developments up to taking an active role in transformation processes fueled by the technological advance, e.g. in favor of sustainable development. In this paper, several role concepts of TA will be discussed against the background of a new framework concept on technology assessment. It will be shown, that TA usually has to take the role of an Honest Broker in assessing new technologies as an umbrella role concept. The specific manifestations of this umbrella role, however, can vary from context to context. The role concept of the Honest Broker serves as an orientation to determine the more specific roles in the tension between assumed neutrality and the obligation to create impact.