The chapter starts with a discussion of the role of mitigation within interpersonal relations. After a brief consideration of similar or related concepts (reinforcement, mood and modality, evidentiality, vagueness, downtoning, and discourse markers), the chapter focuses on the various proposals regarding the classification of mitigation devices. Most of them refer to the scope of the devices. Lakoff's (1972) original concept of 'hedge' was widened by Fraser (1975) and later on by Brown and Levinson (1978), Prince, Frader and Bosk (1982), and Hübler (1983) in order to include not only expressions that qualify the degree of category membership but also those that modify the indication of illocutionary force or the commitment to the truth of a proposition. These distinctions have been further developed and expanded by Caffi (1999, 2001, 2007), who distinguishes between bushes, hedges, and shields. Bushes operate on the propositional content by making referring terms or predicates less precise. Hedges cover both speaker commitment and indication of illocutionary force. Shields can be deictic and nondeictic. Deictic shields shift one of the deictic reference points of the utterance (ego, hic, nunc), e.g., by ascribing an utterance to a source other than the actual speaker. With non-deictic shields, for instance, with a quotational shield, the speaker opens up a meta-level by using expressions like English so to speak or let's say. The chapter continues with an overview and examples of mitigation devices from a variety of languages and is completed with suggestions for further readings.