  This chapter reviews empirical evidence bearing on the design of online
forums for deliberative civic engagement. Dimensions of design are defined for
different aspects of the deliberation: its purpose, the target population, the
spatiotemporal distance separating participants, the communication medium, and
the deliberative process to be followed. After a brief overview of criteria for
evaluating different design options, empirical findings are organized around
design choices. Research has evolved away from treating technology for online
deliberation dichotomously (either present or not) toward nuanced findings that
differentiate between technological features, ways of using them, and cultural
settings. The effectiveness of online deliberation depends on how well the
communicative environment is matched to the deliberative task. Tradeoffs, e.g.
between rich and lean media and between anonymous and identifiable
participation, suggest different designs depending on the purpose and
participants. Findings are limited by existing technologies, and may change as
technologies and users co-evolve.
