The importance of reconceptualising what public service broadcasting [PSB] should be and do in the 21st century is a profile issue in media policy and strategic development planning. There is growing recognition that public participation is a necessary if problematic aspect of the transition to public service media [PSM]. This recognition correlates with a deepening understanding that the viability of the enterprise depends on the people paying for it and using its services. This fourth RIPE Reader demonstrates how the historic insularity of PSB companies is changing in efforts to restructure and revitalise the enterprise. The substance features further development of research presented in the RIPE@2008 conference in Germany, titled Public Service Media in the 21st Century: Participation, Partnership and Media Development. The authors included in this volume query what is required to achieve participation-readiness in many interdependent facets: strategy revision, organisational restructuring, retooling production processes, and redefining professional identities. Approached in two sections, the first focuses on theories and trends and the second on practices and performance. The contents document the significance of engaging the public in, with and through media services, arguing the crucial importance of the Public in Public Service Media.