A painter’s affective state resonates with the intensity of colour. In this chapter, I explore how painters harness the affective and material force of colour, drawing on Bowden’s affective assemblage model of agency. Deleuze’s analysis of Francis Bacon’s paintings is used to establish how colours can be understood as forces that generate or express sensations in the activation of surfaces. As such, I discuss how artists work with colour as they generate spatial effects and produce intensities in an affective assemblage with reference to the Renaissance colouring systems of Cennini and Alberti along with contemporary painters such as Amy Sillman and Lucian Freud. I also draw on Alliez and Bonne’s discussion of Matisse’s qualitative principle that the relation of quantity between coloured surfaces can constitute the quality of colour to discuss Indigenous Australian artist Dhambit Munuŋgurr’s vivid blue canvas. Through an analysis of the work of Tomma Abts, I elaborate the spatial dimensions of painting by outlining the interwoven, multidimensional possibilities of the extensive nature of paint. Closing with how colour may be understood by way of eternal objects and ingressions demonstrates that colours are also caught in multiple relations of force, which inflect the sensations these relations may generate.