The concept of public culture refers most broadly to the dynamic negotiation of beliefs, values, and attitudes regarding collective association through media and other social practices that are defined by norms of open access and voluntary response. The concept is a recent innovation and applies primarily to modern societies, where public culture is the envelope of communication practices within which public opinion is formed; those practices can include news, entertainment, the arts, advertising, social media, and many other means for representing and judging any individual, institution, or custom having collective significance. The term “public” emphasizes relatively unrestricted communication across civil society regarding governance and other matters affecting the general welfare. The term “culture” emphasizes that public opinion depends on contextual factors that emerge through multiple media and embodied responsiveness. These considerations provide a basis for analysis of distinctively modern relationships across civil society, media technologies, and political action in a global context.