The purpose of this publication is to record the current state of the art in research on mathematics-related affect. Research on mathematics-related affect is varied in theories and concepts. Rather than trying to address all perspectives in one chapter, we have identified significant strands of research and invited colleagues from these strands to each write a short section summarizing the state of the art in that strand.The concepts and theories pertaining to the affective domain can be mapped along three dimensions (Hannula 2012). The first dimension identifies three broad categories of affect: motivation, emotions, and beliefs. In this Topical Survey, motivation is covered in Sect. 2.5 (Middleton, Jansen, and Goldin), which also discusses how emotions and beliefs relate to motivation; Sects. 2.2 (Pantziara) and 1.2.3 (Zhang and Morselli) are on beliefs; and Sect. 2.1 (Di Martino) on attitude more or less cross-cuts through all these categories. The second dimension is movement from rapidly fluctuating state to more stable trait. All of the sections in this chapter focus on trait-type affect while only Sect. 2.5 (by Middleton, Jansen, and Goldin) discusses both of these dimensions (referred to as "in the moment" and "long term"). The last dimension covers the theorizing level, which has three main levels in mathematics-related affect: physiological (embodied), psychological (individual), and social. Mathematics-related affect has mainly been studied using psychological theories and consequently most sections discuss only such research. The so-called social turn (Lerman 2000) in mathematics education is in this Topical Survey mainly reflected in Sect. 2.4 (Heyd-Metzuyanim, Lutovac, and Kaasila) on identity, but Sect. 2.5 (Middleton, Jansen, and Goldin) on motivation also has both a section which discusses the social level and how it interplays with the individual level and a section on self-efficacy which highlights the emerging research on the collective efficacy of collaborative groups. The physiological level