Reviewing the extant literature on China's public sphere from the perspective of 20th-century history and social science, this introductory essay argues for the continued relevance of studying the publications and public practices associated with knowledge communities. By steering away from normative definitions and by envisaging publicness as a process, a connection can be explored between social discourses and political practices in China. Discursive communities, based on shared identity or sociability, may appear marginal, but at key moments they can play a unique role in modifying the dynamics of political events.