An affective disposition is an individual’s capacity to affect or be affected in a specific context of affective relations. An affective disposition is constituted by traces of past affective encounters. Such traces act as specific affective potentials in present situations. At the same time, the concrete affective dynamics in which these potentials might actualize are not determined by traces of the past, but modulated and shaped by the affective dispositions of other individuals in the situation. The actualization of an affective disposition is thus a constitutive process. The chapter introduces the concept in the context of a relational and dynamic affect theory based on Spinoza and Deleuze.