Why do people focus on certain issues while ignoring others? Why does politics address specific topics and neglect others? Why do some issues suddenly seem irrelevant, even though they just dominated public discourse? The agenda-setting approach provides answers to these questions. It posits that the way societal problems are highlighted by mass media determines which issues a society prioritizes. This updated and expanded edition offers a concise, easily readable introduction to the theoretical foundations, methodological approaches, empirical findings, and societal consequences of the agenda-setting effect of mass media. It discusses the strengths and weaknesses of the approach as well as its further developments. Related approaches such as priming and framing are also addressed.