Political advertising has always been a contentious issue. In general, this can be explained by the uneasy feeling that advertising, which comes, after all, from the world of commerce, has no place in serious politics. Derived from this, the concern focuses on the presumed effects of advertising on recipients and, in particular, those that go beyond the actual purpose of the advertising (which primarily seeks to affect voter turnout, sympathy for one or the other party or candidate, and the voting decision) and more generally influence attitudes toward politics. Controversies regarding po litical advertising arise in almost every election campaign because its con tent is perceived as unfair to opponents, because it "hits below the belt," or because it violates human dignity. Therefore, concerns about undesirable effects relate primarily to negative campaigning because, unlike the case in commercial advertising, negative advertising in politics is commonplace. Against this background, this chapter summarizes the research on political advertising to determine whether there is a reasonable basis, on the one hand, for the expectations of its sponsors and, on the other hand, for the concerns about its negative effects on target audiences.Political advertising worldwide is a contentious issue. In general, the question whether politics and advertising, which comes, after all, from the world of commerce, are compatible at all arises. Deriving from this, the concern focuses on the presumed effects of advertising on recipients and, in particular, those that exceed the actual purpose of the advertising (effects on voter turnout, sympathy for one party or candidate or the other, and the voter's decision) and more generally influence attitudes toward politics.Controversies regarding political advertising come up in almost every election campaign because its content is perceived as unfair to opponents, 208