Official framing has received increasing attention in social movement studies. Yet current research often focuses on the negative side of framing, that is, how authorities vilify and demonize challengers to justify coercive reactions, whereas little scholarship has scrutinized positive framing, i.e., how officials recognize the legitimacy of citizens' grievances and portray state co-optation or conciliation as responsive governance. Neither does existing research examine institutional foundations of official framings. To address these omissions, this paper devises a conceptual framework of negative and positive framings, which incorporates the examination of a variety of formal and less formal institutions undergirding different types of framing strategies. I develop this conceptual framework through a case study of how a local government framed protest against waste incineration in China. It documents how authorities portray the implementation of an unpopular policy as responsive governance and how different institutions facilitate official frames. An in-depth analysis of official framing not only contributes to the development of studies of frames and contentious politics but to a better understanding of social control and legitimation.