While many aspects of social life possess an emotional component, sociology needs to explore explicitly the part emotions play in producing the social world and human history. This paper turns away from individualistic and anthropocentric emphases upon the experience of feelings and emotions, attending instead to an exploration of flows of 'affect' (meaning simply a capacity to affect or be affected) between bodies, things, social institutions and abstractions. It establishes a materialist sociology of affects that acknowledges emotions as a part, but only a part, of a more generalized affective flow that produces bodies and the social world. From this perspective, emotions are not a peculiarly remarkable outcome of the confluence of biology and culture, but part of a continuum of affectivity that links human bodies to their physical and social environment. This enhances sociological understanding of the part emotions play in shaping actions and capacities in many settings of sociological concern.